Carrier Current Journal

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January 26, 2012 at 4:14 pm #7951

Carl Blare
Participant

Total posts : 1541
Here at kdxradio.com we are planning to install and test a carrier current station and will report the experience here and on the Low Power Hour.
Here at kdxradio.com we are planning to install and test a carrier current station and will report the experience here and on the Low Power Hour.
The first trial will connect us to the electric mains, by which I mean the two “hot” connections and ground/neutral wire, which I think is a “classical” carrier current setup.
As RFB has said, this method may reach a roadblock at the transformer out on the pole, unless there are bypass capacitors, in which case the signal would keep going onward and outward.
There is no visible evidence of bypass gear up on the transformer, and at this time it appears the transformer feeds four or more houses, but we do have automatic metering, whereby the electricity use is measured without need of a human meter-reader, so perhaps there is a bypass.
Also, our AMT5000 transmitter, being radiated by antenna, has a very distinct signal that can be heard in the background for several miles, all along the power lines, and the inventor, PhilB, estimates that this can be explained by unintended carrier current emission, which, if true, is another hint that our transformer is bypassed.
January 26, 2012 at 10:53 pm #24366

RFB
Total posts : 0
There may be slight effects off nearby power lines at short ranges from a 3 meter stick with 100mW on it. However it’s not going to go several miles as “loose” coupling via some wire near an electrical conduit, the signal will get absorbed rather quickly.
Most likely this is happening because you have your transmit antennas (wire) hung inside the house along a wall near a window with a romex line nearby and that is picking up the signal and the use of ground off the outlet or your equipment ground, which probably the ground path is radiating more than the wire is, thus will cause some CC effect.
With your latest acquisition, you can do CC for real and not have a side effect CC from a piece of wire.
Just remember that there IS a big difference between the neutral and ground of the AC grid, as well as in your breaker box and outlets.
ISOLATED EARTH GROUND:
If your breaker box is the primary “break” point after the mains leave the meter outside, the neutral (white) and Earth ground (green) will be connected together within the breaker box.
There may even be a grounding wire ran from the meter box down into the dirt attached to a buried ground rod, or connected to the cold water main service into your house.
Start probing around between the cold water main and the utility ground/neutral. Hopefully it is isolated. If not, then installing ground rods will be your only choice for the isolated ground.
Coupling to the “hots” is extremely dangerous and should be done very carefully. There will always be that 220vac potential inside the coupler, and never never NEVER run an isolated ground path to the coupler when coupling to the “hots”!!! Not unless you want to create a new ground path for lightning strikes and voltage spikes. POOF!
Become familiar with your breaker box, its wiring configuration and use a 220 breaker at the least amperage rating possible for quickest flip response time of the breaker in case of a problem. 220vac really is not that much voltage considering 7,000 and up rides on those upper wires on the grid. But the amperage capacity on those two “hots” is well into 150+ and that is what is the killer.
Place a rubber mat on the floor in the work area where the TX and coupler will be installed. This will help to keep you from becoming a human ground rod in case of accidental contact with one of those hots. And I would keep that rubber mat there even after installation so that way if you had to re-peak the coupler, or check connections, your standing on isolated surface instead of cement or other hard surface that could become conductive from moisture. Had a friend who learned that lesson the hard way and now his entire right arm is disabled and looks like a twisted tree twig. And that was working around the 220 single phase hots. Imagine what 440 3 phase will distort!
Good luck and keep us updated. If we see a mushroom cloud, we will disavow any knowledge of your mission and existence and declare it a freak accident. 😉
RFB
- January 26, 2012 at 11:46 pm #24367
  
  Carl Blare
  Total posts : 0
  Thanks RFB:
  ELECTRIC SERVICE
  A couple years ago I had an ancient 60 Amp power box replaced by a modern high Amperage box, I forget, either 150 or 250 A.
  The electrician who did the install was like a stage magician. With no help whatsoever, he followed my instruction to move the box from a corner to a more central spot on the basement wall, and he quickly whipped all the old and new wiring over to the location and had it finished.
  The neutrals are grounded in the box, like you said. According to code, there is a giant twisted copper wire that traverses the basement over to the water pipe where it is grounded.
  The twirled 3-conductor “drop”cable out about 100′ to the pole does not see ground again until it reaches the pole.
  There are no ground rods around the house/property.
  The first installation site is already to plug in without the need for dangerous wiring, it is a large 3-flat-blade socket which belonged to the drier. My only part will be to wire a 3-blade plug to the coupler for connection.
  Your suggestion of going low-Amperage on the circuit breaker will be taken care of before it is turned on. Thank you for that.
  Guess what? The doorbell just rang, and it’s the LPB Coupler from the eBay auction! It got here right away.
  - January 26, 2012 at 11:58 pm #24368
    
    RFB
    Total posts : 0
    Glad to see the coupler made it so quickly and intact.
    TIME TO PARTY!!!
    Well wait…not so fast!
    I can only imagine that your sitting there glaring at the TCU-30 coupler and dreaming of millions and millions tuning in!
    Isn’t radio fun!
    The dryer outlet will make a good coupling point for your first attempts, and be a lot safer than tinkering around inside the breaker box. I am assuming this unused dryer outlet is already fixed with it’s own breaker in the breaker box?
    If not, it should be.
    Also will this area where the coupler and TX will be..is it fairly well ventilated? In other words, it doesn’t get too hot in that room with washer and dryer running. A small fan will help vent out the warm air inside the TX through its vent holes and keep things cool.
    When the TX 2-20 arrives, be very careful of that power adjustment pot. DO NOT ATTEMPT TO ADJUST THE POWER WHILE THE TRANSMITTER IS TURNED ON! That power adjustment pot is incredibly sensitive to external inductive objects such as your hand, and will make the power spike upward like a shooting rocket, and potentially blow out the finals.
    Begin with the power pot adjusted 1/4 turn from its lowest setting, and adjust in steps after that between power on and power off cycles.
    To solve the issue of the sensitive power pot, simply replace it with a flat surface mount type so you can use a tuning tool directly above the pot instead of the original sideways mounted pot. Replacing the pot with a flat surface mount pot solves the sensitivity problem in all of them, and you can then adjust the power while the TX is running.
    More tips later.
    RFB
    - January 27, 2012 at 12:26 am #24369
      
      Carl Blare
      Total posts : 0
      The drier outlet does have it’s own circuit breaker, but I will need to change it from 30-Amps, or whatever it is now, down to the low Amperage you recommended.
      The basement is cool and there is no drier, since I use the good economy of drying clothes using free air and coat hangers.
      Thanks for the power control tip on the transmitter.
      The unit inspects to be in good condition. The “scratch” on the meter is more of a superficial streak, it is not etched into the plastic.
      The power screw-terminals look weathered, but a little Dioxit will clean them up.
      A neatly printed schematic is included, but no instructions for calibration.
    - January 27, 2012 at 4:40 pm #24376
      
      Carl Blare
      Total posts : 0
      Looking at the ATU-30 Schematic it is easy to spot the connections for neutral, line, line, and …….. there is a connection for a 3rd “line” but that will go unused.
      Therefore the first installation, using the dryer 220-VAC plug, will be simple. The hardest part will be changing the circuit breaker down to a low Amperage, but I’ve made circuit breaker changes before, so it will be familiar work, with extreme care.
      What I do not know is how to use the various controls on the coupler, starting with “calibration.”
      The meter offers somewhat of a clue, as it has several scale-markings, the topmost being a setting for transmitter input Wattage, up to 30-Watts.
      The lower scale consists of a short green strip, which I guess indicates a minimum SWR (standing wave ratio) and a larger red space which probably signals that the SWR is too high and needs to be reduced.
      There are 3 switch settings that will need explaining, “Test”,”Calibrate”, and “Power.”
      There is a silver sticker on the coupler saying “AVOID UNIT DAMAGE. DO NOT LEAVE IN “POWER” “CAL” OR “TEST” FOR MORE THAN 3-MINUTES.”
      I also remembered only this morning that I never asked what frequency the transmitter is set for, but I’ll need to get a crystal for 970kHz, so there is another detail.
      Lunch?
    - January 27, 2012 at 10:56 pm #24378
      
      RFB
      Total posts : 0
      LPB divided the MW band up into 3 sections and made low pass filters for each of these 3 sections of the MW band.
      Low-Mid-High
      Low is 530-830
      Mid is 830-1270
      High is 1270-1710
      I think that 2-20 unit was set up originally for the high section of the band and then changed to operate for the low section of the band, but you will have to check with Tommy on that to make sure.
      It’s is not difficult to change the LPF components to work another section of the band. Just about every TX manual of these series has the LPF part chart for the 3 filters used.
      On to the TCU…not ATU. You will not be using this or that RS CP-15 as “ATU’s”. Although both can certainly be used as an “ATU”..they are not intended for that purpose nor can either of them couple up to a 10 foot wire. The wire would have to be at least 120 feet long and the coupler would require an isolated Earth ground system kin to that of a MW broadcast tower’s ground system.
      There is a way to get them to couple to a short wire..but I’m not going to disclose that to end up being the suggestion source when someone get’s tagged for exceeding 219.
      On with the coupler:
      The TCU 30 coupler has 3 main adjustment controls. Going from left to right, two of them are for the capacitance decade. The third is for the inductance range.
      The lone wolf control below the 3 above is a function control with 4 positions. “POWER”, which is the first step and position this control must be in to begin the tuning process.
      “CAL”, which is “CALIBRATE”, is the second step in the tuning process. Once you set the power level on the transmitter with the TCU’s function switch in “POWER” and reading the indication on the on-board meter which will indicate your RF power out of the transmitter, the function switch is then turned to “CAL” and you adjust the “CAL” variable control to set the meter to FULL scale.
      The next section of the function switch is “TEST”. This position of the function switch lets you see your tuning on the meter. You tune for lowest SWR by rotating the inductor selector first, then the 1000pf decade control, then finally the 100pf decade control. Then you repeat the process from the inductor selector, to the 1000pf selector, then the 100pf selector for minimum SWR on the meter.
      Once you adjust for lowest SWR on the meter (needle in the green), your ready to move the function selector to “OPERATE”.
      The RS CP-15 has two inductor selectors instead of one. This gives you a little bit more inductance range and a little more capacitance decade range. I found no real useful benefit of the extra inductance and capacitance range in the CP-15 versus the TCU-30. The CP-15 unit was really intended for TIS applications and night time power operations of licensed stations. It just so happens that both the CP-15 and TCU-30 can serve both CC systems and short tower antennas.
      The setups for the CP-15 are the same process as the TCU-30 with the exception of the extra inductance and capacitance ranges.
      RFB
    - January 27, 2012 at 11:07 pm #24379
      
      Carl Blare
      Total posts : 0
      If I am right about this that would make me smart.
      I am thinking that maybe the DataKit 80-035 PLL-EXP1 Experimenters Package can be used in place of a crystal to put the 2-20 Transmitter on 970kHz in the mid-band. Huh?
      GOOD, now I will print out the Instructions for the TCU-30, and I downloaded the manual for the CP-15, so we are very close to carrier currency.
    - January 27, 2012 at 11:42 pm #24381
      
      RFB
      Total posts : 0
      Yes. The DataKit PLL can be used to replace the crystal and its oscillator IC. You will need to make an oscillator that will either operate at the 6x frequency, or one that operates on the intended frequency and not use the divide counter IC.
      On the exciter board there is a test point below the meter labeled “FRQ TP”. This is where you would inject the oscillator signal if the oscillator is operating at the intended frequency. If the oscillator will operate at the 6x frequency, you need to leave the divide counter chip in the circuit and inject the PLL oscillator into the divider chip, exact pins forthcoming.
      ADDED:
      To inject in-band oscillator frequency, remove IC “A2” and “A3”. Inject the oscillator signal at PIN 8 of IC “A3″‘s socket, or at the FRQ TP stud.
      To inject a 6x frequency, create the crystal equivalent with a tuned circuit and keep both “A2” and “A3” IC’s in circuit. Use the crystal socket as a mounting point for the small PC board containing the oscillator circuit being PLL’ed by the DataKit.
      Remember, ALL of the solid state LPB’s use a frequency that is 6 times than the intended operational frequency.
      For your frequency of 970Khz, you would need a 5.820Mhz crystal, or a tuned circuit capable of oscillation at 5Mhz and let the PLL do the rest.
      NOTE: When using the PLL to operate on the intended frequency, punch in the intended frequency on the keypad…ie for 970khz punch in 000097. For the 6x frequency, punch in 005820.
      RFB
    - January 28, 2012 at 12:39 am #24382
      
      Carl Blare
      Total posts : 0
      You solved another puzzle with the information about using the PLL Circuit in place of a crystal. Now the next question.
      In the Instruction Manual, page 4.0, it says:
      “It is important to note that the TX-2-20 Transmitter MUST be used with the T-8 Power Line Interface.”
      This covers ground covered before on this thread, but I only now see this STERN INSTRUCTION and therefore ask once more if we are still safe with the TCU-30 Coupling Unit.
    - January 28, 2012 at 3:26 am #24384
      
      Carl Blare
      Total posts : 0
      RFB wrote “LPB divided the MW band into 3-sections and made low pass filters for each of these 3 sections of the MW band. Just about every TX manual of these series has the LPF part chart for the 3-filters used.”
      But not the Manual for 2-20, which has no description of the 3-different bands.
      The only clue that something special is going on are several parts in the parts list shown as “Factory Select.” Of the 6 such parts there are 2, namely C25 and C37 which say “Frequency Dependent”.
      The only thought I have is that LPB tailor made the 2-20 for particular frequencies.
      I will consult with the seller (Tommy J.).
    - January 28, 2012 at 4:36 am #24386
      
      RFB
      Total posts : 0
      The manual I sent is specifically for the exciter board type used in your particular version of the TX 2-20.
      The power amp section is the same as the AM-25/30 and what is used in the combined transmitters forming the 60/100 P models.
      I will send you the manual to the AM 30 which does have the filter component chart and parts list which are applicable to the power amp module in your TX 2-20.
      At the time of the publication of the TX 2-20 manual I sent you, and the model released at that time, covers the exciter type that you will find in your TX 2-20 unit. And at that time, the coupler then was the T8.
      Don’t worry, your TX 2-20 will work perfectly with the TCU-30 or CP-15.
      RFB
    - January 28, 2012 at 4:05 pm #24392
      
      Carl Blare
      Total posts : 0
      I printed the low pass filter data from the AM-30 Manual and compared it to the 2-20 Unit, and just like you said, an exact likeness.
      The caps, C31 to C35 have the same numbers, the chokes or coils have different part numbers but refer to the same parts… L4 = L2 and L5 = L3
      Wow, it’s lucky that LPB printed this info, because elsewhere in the AM-30 Manual they write,”To change the band of operation return the transmitter to the factory.” Whoever wrote that was optimistic about the future.
    - January 28, 2012 at 6:44 pm #24396
      
      RFB
      Total posts : 0
      Well at one time they were the best choice to re-frequency these transmitters, although changing the frequency and LPF components require no greater than a skill level 1.
      It was more of an advertisement offer than an actual technical requirement. It was also a reminder to those who had these transmitters still under warranty and needed the frequency and band change.
      Yes, there are a few of the LPF components that are the same for both the low portion and mid portion of the band. The only one that is the lone wolf which uses different parts all the way through is for the 1270-1710 segment.
      It made sense for LPB to start using the same power amp board and components for all of their solid state units. The only unit that uses different finals, but still uses the same PC board, bias, bypassing and filtering is the TX-5 from 92 up. The finals are smaller cousins to the SD1407’s, specifically they are SD1285’s.
      This approach by LPB also made it practical on both their part and for the end user to have interchangeable modules, cutting down their manufacturing costs as well as cutting down the costs to the end user.
      As to the energetic employee who wrote the note of returning the unit to the factory for a frequency/band change…well that was during an era of prosperity, jobs a plenty, industrial growth and manufacturing, the 80’s version of “Happy Days”.
      No such thing these days…except manufacturing toothpicks and paperclips…..with imported raw materials.
      RFB
    - January 29, 2012 at 12:04 am #24403
      
      mram1500
      Total posts : 0
      Carl I bought a TCU-30 a few years ago and it came with the manual. It’s complete with setup instructions, schematic, parts layout, etc.
      If you’re interested I can scan and make the info available.
      I also have a Radio Systems Phase II 20 watt transmitter which came with some info regarding the transmitter and their CP-15 carrier current coupler if anyone is interested.
      When I bought the Phase II it was on 640 kHz. I ordered the parts kit to modify the amplifier section moving it to 1500 kHz. I have the instruction sheet for that mod also.
    - January 29, 2012 at 12:48 am #24404
      
      Carl Blare
      Total posts : 0
      Riches are not embarrassing.
      What a great offer from MRAM, but I think you can be spared the effort it would take to duplicate and post the lit, and here’s my ultra practical thinking, unless someone convinces me otherwise…
      The TCU-30 Coupler came with a schematic, and RFB has sent very detailed setup instructions, and unless there is more to know than those two things, a copy of the Instructions would probably be redundant.
      Another advantage came in the fact that Radio Systems has the manuals posted online for the TR-20 Transmitter & CP-15 Coupler, and an additional CP-15 Coupler Manual.
      Therefore, as far as I can tell, I have all the literature that will be needed.
      By the way, how do you employ the TR-20?
      It appears that Radio Systems no longer sells the Tr-20…. why would they discontinue it?
    - January 29, 2012 at 2:11 am #24405
      
      RFB
      Total posts : 0
      “t appears that Radio Systems no longer sells the Tr-20…. why would they discontinue it?”
      Old model…in comes a new model with newer components, newer design, etc etc.
      Ironically…those older RS units sure do have a striking similarity in the circuit designs and components as do the LPB units..including the couplers.
      The older RS units show up on auction now and then as well.
      The thing is…these two companies..back in the day and in their prime, were doing very well selling these things, but they were not selling them to the everyday joe putting up a Part 15 station at home. They were sold to colleges and universities and drive-in movie theaters and amusement parks and national parks like Carlsbad Caverns and Yellowstone…tourist/visitor info stuff..then along came the TIS(k) TIS(k) stations around the time of LPB’s steady demise and eventually RS being the only player, and by that time the colleges and universities moved on to licensed non-commercial FM and sold off their LPB or RS stuff.
      RFB
    - January 29, 2012 at 3:00 am #24407
      
      Carl Blare
      Total posts : 0
      If there is a “bug” on my website is it likely caused by some file or code slipped onto my website?
      About a year ago I found that almost all of my html pages at the site had some unknown code added which I knew nothing about. I still don’t know what it did, but I erased every instance of it.
      I will do another sweep to see what there is to find.
      Of course now there is another enemy of the average website besides all the civilian and nationalistic criminals, and that is our “own” nation, be it in military or statutory form, selling our organs to the highest bidders on the world market.
      Any idea where I should be looking?
    - January 29, 2012 at 3:21 am #24408
      
      mram1500
      Total posts : 0
      Carl, I’m not using the Radio Systems Phase II transmitter at this time.
      The Phase II came from a University somewhere around the east coast. I bought it to try out Carrier Current. The University listed several of these on Ebay. They were part of a network of Carrier Current stations they operated. The one I bought as mentioned previously was crystaled for 640 kHz which locally is the AM station WHLO in Akron, Ohio. Cost: $125
      I obtained a parts kit from Radio Systems to move the transmitter to the upper end of the BCB and put it on 1500 kHz. The kit contained the torroids and capacitors for the output network. The crystal was also included in the purchase. Cost: $125
      Some time after, I picked up a TCU-30. I haven’t made a serious attempt at Carrier Current yet, simply putting an AC line cord on the neutral and phase 1 input and plugging it into an AC outlet. Cost: $205
      So, for now the pair are just hanging on the wall in my shack.
      I manage our City’s AM TIS WQGD298. I employed the Phase II transmitter briefly at the station when the ISS transmitter was down for repair. The City sprung for the crystal on 1650 kHz and the transmitter performed perfectly. It was on air there for about a month.
    - January 29, 2012 at 3:39 am #24411
      
      Carl Blare
      Total posts : 0
      Dear Employer:
      Your transmitter is down for service, but I just happen to have a transmitter that can keep you on the air while I fix yours.
      That looks good as a plus of having you as their fixer person.
      I do hope they understood and appreciated what had taken place.
    - January 29, 2012 at 8:33 pm #24419
      
      Carl Blare
      Total posts : 0
      In the pre-planning stage as we get set to install a carrier current system, made much easier by all the good help from members here at part15.us, we are reviewing our frequency selection in light of two facts:
      FACT 1: All the literature says that carrier current works best down below 800kHz, the lower the better;
      FACT 2: For operation above 830kHz the low pass filter in the transmitter output stage must undergo the changing of five parts, because the transmitter is presently wired for low band operation.
      THEREFORE, I am wondering two things:
      THING 1: Am I absolutely sure there isn’t a spot on the low band so we could avoid changing five parts?
      THING 2: As long as we are changing the output low pass filter maybe we could install three filters with a selector switch for low, medium and high band?
      ANYWAY, let’s retrace our low band frequency search:
      520 Many AM radios will tune 520kHz, however the carrier current rule, 15.221, only allows 525 – 1705kHz;
      530 This is often used by TIS (traffic information service) and was used locally by an Illinois traffic service, but lately is bringing the audio from a licensed station on 1430kHz. It doesn’t matter either way, however, because there’s only one guard channel above this frequency;
      540 Usually blank, but directly adjacent to a powerful station;
      550 local 5kW station;
      560 open, but too close to 550;
      570 usually open, with an occasional time station from Cuba;
      580 open, but crammed by..
      590 1kW local station directional toward here;
      600 blank;
      610 blank;
      620 blank;
      630 5kW local;
      640 blank
      650 WSM 50kW Nashville TN;
      660 blank;
      670 blank;
      680 blank;
      690 local 1kW
      700 WLW 50kW New Orleans LA;
      710 blank
      720 blank daytime, WGN Chicago night;
      730 1kW just out of town daytimer;
      740 blank;
      750 blank;
      760 blank;
      770 10kW local;
      780 WBBM 50kW Chicago IL;
      790 blank;
      800 blank;
      810 blank;
      820 blank;
      830 WCCO 50kW Minneapolis MN;
      840 blank;
      850 5kW daytime only one-mile away.
      What about 800kHz? Maybe that could work.
      NEVER MIND. I just went to 800kHz and found a blaring phantom of the 5kW nearby station on 850kHz, whose HD Radio buzzsaw extends over 830, 840, 860 and 870kHz.
      740 might be good. The out of town station at 730 is far enough away that probably no one here listens to it.
    - January 29, 2012 at 11:14 pm #24422
      
      RFB
      Total posts : 0
      Well all of the literature at the present time was written years ago, some as much as 30 years ago and more, when the grids were configured differently. Even at those times, there were CC type baby monitors and in-home intercom systems running on 1.7Mhz and some even as low as 1.2Mhz.
      Now those systems worked just fine on the electrical wiring and they were not 800Khz and below (.8Mhz)
      In some cases, a CC system will perform better on the upper band, or the middle band and sometimes not work well at all on the low band. This is what I have been saying for the last several months that CC systems is a science in flux, meaning that there is no one solid gold rule or technique to ANY CC installation. They will ALL be different and require different approaches, even when selecting a frequency to operate on. In some cases, operating in the low band works, while in others, the mid band or upper band works better.
      To avoid the swap out of filter parts, I would find you a frequency on the low band first and install the system and begin tests. You have from 530 to 830 to experiment with the current filter in the TX. Your list shows PLENTY of open low band channels available. Make it easier on yourself while you learn the ropes of a CC system and work with what you have on hand and conduct tests. Then if you see a need to move to the mid band or upper band, at that point make the change. Be a shame to go through all that work of changing out filter parts, the costs, downtime or risk of messing something up, and find out that change was not a good idea because the change to mid or upper band doesn’t work with your grid configuration! All that work for NOTHING!
      There is an old saying in the engineering field: “why make more work for yourself?”.
      About 80 percent of LPB’s orders were for transmitters built to operate in the low portion of the band..ie 530 to 830. It allowed the signal to travel down the buildings wiring more efficiently and gave a cleaner signal at the reception ends, especially if there were a lot of splitters and booster linear amps working against high inductive loads such as elevator motors, space heaters, air conditioning compressors and florescent lighting. These things wreaked havoc on CC installations. The low portion of the band is somewhat less prone to these inductive loading problems, but it all depends on the location of these external loads on the electrical system and where the CC system is injecting the signal onto the electrical system.
      It’s a big venture, MUCH bigger than a simple dangling wire from the roof or taped to a window or tuning up a 3 meter outdoor antenna. And the solutions are NOT going to be written down in some tech note somewhere. Most of what was discovered from site to site was kept to either the person installing the systems, or the owners of the systems and chances are those notes are long gone and buried in some land fill somewhere. This is why we see very little information about CC on the web, or anywhere else.
      Basically these days, CC must be relearned and re-documented as it once was back in the hey day. We can use that literature from decades ago as reference, good starting points. But most of it is so outdated, that only bits and pieces of the old literature is applicable for today.
      Get ready to go to school..YOUR own school..because class is about to begin and guess who is the teacher….YOU! 😀
      ADDED: You will also find that it is NOT necessary to operate that transmitter at it’s full output power. It may only take a couple watts or so, perhaps a little more. But the thing to always remember is that a CC system does not rely on large distances of air between transmitter and receiver. The signal is riding on the power lines which run into people’s homes and businesses. It’s like taking your 3 meter antenna and putting it next to everyone’s radio via the power lines. So naturally you won’t need to shove so much signal down the lines and saturate everyone’s radios within the first block! Start with a couple watts or so and work from there until you find a good enough power setting for good coverage. Even the LPB manuals state this..and the inspecting FCC agent will also advise you that you only use just enough power to get a clean signal but not so much your saturating radios all over the dial and jamming up the cable system or POTS with intermod. Remember, their lines are right below the power grid lines your signal is on and if too much signal is there, can and WILL make its way into the cable distribution line as well as the telco cabling.
      RFB
    - January 29, 2012 at 11:46 pm #24424
      
      RFB
      Total posts : 0
      “THING 2: As long as we are changing the output low pass filter maybe we could install three filters with a selector switch for low, medium and high band?”
      When your TX 2-20 arrives, look around that final amp module and where the filter parts are. Do you see room in there for 3 sets of filters and the inter-connecting for a switch which will have to have 3 x 2 plus 1 contact points?
      NOPE!
      Besides that, putting so much cluster of inter-connecting lines to 3 filters via a 3 position switch which must have 3 in and 3 out plus 1 common ground contact will create nothing but a cluster of potential pathways of the high RF level in that area, seriously affecting the impedance of both the final elements as well as the output point going to the small coax which feeds the So-239 jack on the side.
      The BETTER approach..which I have already done, is to build 3 filters onto 3 double sided full plated PC board and use dead bug or Manhattan style construction and feed-through PC mount studs so each module can simply be inserted onto the PC mounting studs already present on the final amp module.
      Space the new feed-through studs on the new boards so that the entire thing simply slides into the existing studs, like as if plugging in a module into a pattern of holes on a board.
      Works great and is useful for the testing phase to find the right portion of the band to work in…and saves a lot of headache on soldering and un soldering of those filter parts, and prevent a solder mess or over-heating of the existing studs and their soldering. It also keeps the filter toroid parts close to the ground plane of the final amp module, which DOES play a role in the filter’s effectiveness AND characteristics. So you will want to keep that in mind regarding that filter section. Some of the transmitters will have those toroid transformers standing on their edges, and others will be laid down flat on the ground plane surface of the final amp module, all of which plays a role in how that filter functions.
      RFB
    - January 30, 2012 at 12:12 am #24425
      
      Carl Blare
      Total posts : 0
      You said there are a lot of open channels on my chart……
      But, did you not also say at one time that there must be 2 guard channels on either side?
      If I used 530 as you suggested, there’s only one guard channel at 540.
      On the other hand I do plan to try 570, even though there’s only one guard channel on either side.
      And I do want to run it on the low power side, to draw very little attention. I will start be having that “out of town sound.”
      I had not previously realized there could be induction into phone and cable……yikes.
    - January 30, 2012 at 1:15 am #24426
      
      RFB
      Total posts : 0
      “But, did you not also say at one time that there must be 2 guard channels on either side?”
      I stated the standard MW band channel separation between stations is 30Khz, and that it would be ideal to follow that same channel spacing…ie “guard” space on each side of your operating frequency. It does not, nor did I mean that a CC system must follow that standard, but is as I put here and before…ideal.
      But sometimes we do not have 30Khz of headroom above us or 30Khz of catch net below us, so we have to “improvise” and “overcome” and “adapt” and be nice and find a frequency which will cause the least interference, both co-channel and IF intermod, as well as the cable and telco systems.
      “I had not previously realized there could be induction into phone and cable……yikes.”
      Well let’s think about all of this for a moment.
      Where are those power grid wires?
      Where is the cable TV distribution line?
      Where is the telephone system cabling?
      Yes yes, some of that these days run underground..especially in big cities. All the same however, they all are in close range of each other along their distribution paths from source to end user/customer.
      Now let’s throw in “inductive coupling”, which does happen even with a piece of wire strung off the roof or in a window pane.
      Put two and two together and what do you have?
      BTW..CC works by “inductive coupling”. :p
      So you see…CC is not as simple as it seems or as simple as stringing up a wire across a wall held up by pictures over the hallway entrance or connecting to a window pane frame. In such cases, inductive coupling does occur but at a very small level…ie wrapping a 10 foot wire that came with your AMT5K around an extension cord plugged into an AC outlet, or that same wire sending signal through your house while that signal passes through walls and wiring catching that signal like catching a school of fish with a drop net.
      In a REAL CC system, your using a device specifically designed to inductively couple your signal onto the electrical wiring in a MUCH GREATER efficiency factor than the wrapped wire around the extension cord or through the air capture of a nearby signal. Therefore, the chances of causing interference to other services such as cable TV distribution and telco systems is even greater.
      Like I was saying….class in session.
      Anyone else wish to sign up for the class? 😀
      Carl, the best approach per your frequency chart is to begin on a frequency that has at least 20Khz above spacing from your intended frequency of operation, and begin with low power settings, say 5 watts or less so you can tune up without overheating the load resistors in the coupler as you tune, and to keep from shoving too much RF down the lines as your trying to measure any interference. It could be too much RF power that can cause the problem, so start out with low levels and create a chart or graph for good coverage power levels versus power levels making everyone’s phone’s sing and dance…along with their tv’s! LOL.
      RFB
    - January 30, 2012 at 5:47 am #24428
      
      Carl Blare
      Total posts : 0
      Based on good advice and from general life experience, we will start out with 2-Watts, this transmitter’s lowest setting.
      At 570 there will be an empty channel 10kHz wide on both sides.
      “Brought to you by The Electric Company.”
      ADDED NOTE LATER THAT SAME EVENING –
      11:40 PM CST the Cuban Time Station is banging in at 570kHz, louder than ever
    - January 30, 2012 at 10:00 am #24432
      
      RFB
      Total posts : 0
      I would use the following frequencies to test and find one that will work.
      570
      610
      670
      750
      810
      You said on 570 some Cuba time station comes in now and then.
      I doubt anyone around your area is going to be too concerned about a CC station transmitting on top of it. I doubt that when it does come in via skywave, it would be a problem for your CC system.
      RFB
January 30, 2012 at 7:38 am #24431

MICRO1700
Total posts : 0
Hi Guys!
I’ve been reading this with great interest.
Again, it goes back to my good good friend in New Jersey.
I am beginning to sense that his life may be more
over loaded than I thought. He has the LPB RC-6A
and an SS Tran AMT-3000. Both of which are mine,
and as you all know, I’ve been trying to get them
back. The SS-Tran is my second one, as yet not
assembled. I got it as a spare a couple of years
ago.
It is not like him to be unresponsive. He has
recapped some old radios for me, fixed some ham
gear, and he even built me a wonderful 80 meter
one tube cw transmitter, which is beautifully
made and works great.
I just sense that he is REALLY in the middle of
things – too much life, I guess. Maybe he has
something in his life that really isn’t good –
and I just don’t know about it.
So I will just keep gently trying to remind him
about the gear. He is SUCH A GOOD FRIEND, I really
don’t even want to bother him, if he is going through
tough times. I have known him since 1976. He is
really one of the finest people I know.
So cross your fingers for me. If I could see well
enough to drive, I would just go there and get the
stuff. I would ask my wife, but I know there is
no way she would drive a 200 mile round trip to
pick up a couple of radio transmitters.
Again, keep crossing your fingers for me, and I
will continue to read this thread with great
interest.
Best Wishes,
Bruce, DOGRADIO STUDIO 2
- January 30, 2012 at 11:27 am #24433
  
  RFB
  Total posts : 0
  “I’d Like To Be in The Class – I Just Don’t Have The Transmitter”
  That’s ok…no TX required!
  When your R6 arrives, then you will be ahead of the game and be able to jump right in and get your CC going!
  RFB
January 30, 2012 at 4:01 pm #24435

Carl Blare
Total posts : 0
The idea of sending intelligent human information over electric power lines seems like an episode of The Outer Limits.
“The wires are talking.”
I am having an undress rehearsal (as opposed to a dress rehearsal) this morning for the moment when the LPB2-20 Transmitter & Coupler arrive from Texas. There will be a “ding dong” of the doorbell, I will open the door, and the box and a Fedex guy will be there, or maybe he’ll be half-way back to his truck by then, and I’ll say “Thanks!” I’ll bring the box indoors thinking, “hmm, it’s lighter than you’d expect,” and set it on a small table while finishing a cup of coffee. Then I’ll calmly open it up. If there are crumpled-up newspapers as padding, I’ll unfold each page and read it front and back.
To be continued.
- January 30, 2012 at 6:03 pm #24436
  
  Carl Blare
  Total posts : 0
  Part 2 – The Inner Limits
  Last week Ultanium supplied a Tracking Number so that my office staff, that’s me, could play the real-world computer game of Tracking.
  Since I was here wondering whether I should dress better for that 2-seconds greeting the delivery person, I decided to Track.
  The giant Fedex Computer knew exactly what was happening. According to it, the package moved from Bryan, Texas to Hutchins, Texas, and from there started a serious “in-transit” status on it’s way north to Missouri.
  The Tracker estimates that delivery will occur on the 31st, which is tomorrow. That’s a relief. I can think about something else today.
  To be continued.
  - January 30, 2012 at 6:57 pm #24437
    
    kc8gpd
    Total posts : 0
    the nj economy has gone to hell. average rent for a 1 BR apt no utils included is 1300/mo and there isn’t near enough jobs let alone good paying ones to go around. the ny people has moved out of NYC buying multimillion $$$ mansions on postage stamp size lots skyrocketing taxes and rents. my friend works 80+ hrs just to make his 20k/yr tax bill on his small piece of property, then don’t even get me started on southern jersey with the tourism causing a spike in the cost of living.
    your friend probably isnt doing it intentionally he is just busy trying to keep food in his mouth and a roof over his head. yeas things are that bad. nj is like a little california.
    - January 30, 2012 at 9:14 pm #24440
      
      RFB
      Total posts : 0
      “the nj economy has gone to hell..your friend probably isnt doing it intentionally he is just busy trying to keep food in his mouth and a roof over his head. yeas things are that bad. nj is like a little california.”
      It’s bad everywhere and no relief in sight. As long as the puppets up in DC continue doing what they are doing under the direction of the elite, nothing is going to change.
      They will keep smiling, waving and fooling the masses, and as usual..the masses buy it hook line and sinker.
      The problem is not really in DC or with the elite..the problem is the passive public convinced everything is just fine and dandy…while crying over the piled up bills and foreclosure notices.
      It’s like that debt consolidation commercial with the guy on the riding mower in his front yard..smiling as if everything is sunshine and birds chirping…but mumbling to himself “I am in so much debt…”.
      It’s one thing to recognize the fake reality we are all forced to live through, but its something different, and a big problem when the majority live in denial and pretend the gangster behind the podium is incapable of deception or ever will deceive.
      Yet it happens daily, right in front of everyone.
      Ironic…and quite disturbing.
      RFB
    - January 30, 2012 at 9:27 pm #24442
      
      Carl Blare
      Total posts : 0
      Mitt has been complaining about what a spoiled brat Neut is. And Neut is airing a dirty laundry basket from Mitt. They each want the presidency as trophy toys they can dicker with from onboard a yacht turning the Nation into a play hobby.
      Numbers are part of any game. Homeless numbers are something to check daily as the hobby unfolds. If the number goes down for some reason, it’s time to make an announcement: “Homeless numbers are on the decline! Thanks for your vote.” But if the numbers go up, it’s time to check the evening’s menu.
    - January 30, 2012 at 10:21 pm #24443
      
      kc8gpd
      Total posts : 0
      things are good in denver and the pay rate reflects it, as long you have a degree in medical or tech fields. at least until people flock here from out of state and fill up all the available positions.
    - January 31, 2012 at 1:53 am #24455
      
      RFB
      Total posts : 0
      These days it’s even more necessary to be extra creative. And Part 15 radio can help with that in many ways.
      Right now I do voicing for commercials on the local stations, right from my own studios. They send me copy, instructions and I do the rest, send them the mp3 and score 20 bucks per spot.
      Today I made 40 bucks for about 10 minutes of work.
      Unfortunately the cycle of doing voicing for commercials is low, as expected since even businesses are struggling just to keep their doors open and a staff on hand. A lot of local businesses are doing a lot less advertising so that is another damper in things.
      My FM and CC AM stations run a few local advertisements here and there as well, and run a few spots for individuals selling items at their yard sales. The radio spots lets them announce ahead of the yard or garage sale what they have for sale.
      It’s no grand and a half a week that’s for sure. But it is a little something that does help a great deal overall.
      RFB
    - January 31, 2012 at 2:20 am #24456
      
      Carl Blare
      Total posts : 0
      I love your side work, RFB, cutting spots for pro use. Two suggestions for building business:
      1.) expand out of market. Using the telephone and internet find other radio stations all over the place who can benefit from having a voice service. This could really add up to a busy shop;
      2.) Cut “spec spots” for the sales staff. That’s what I did a few years ago. The sales manager would send me copy for clients they were trying to sign, I would cut “spec spots,” and this helped the buyer envision how his commercial would sound, and it made sales grow for the station. Of course the station paid me for this service.
      Also, ad agencies and corporations often do Power Point Programs for all kinds of reasons, and voice can be added to those. I’ve done plenty.
      Oh, and TV stations need voice breaks cut everyday.
  - March 27, 2012 at 1:48 pm #25461
    
    Carl Blare
    Total posts : 0
    Hello Carrier Current Journal readers.
    Yes, this is the new online news zine, The Carrier Current Journal.
    During the first few days of full time carrier current operation, KDX CC ran on 2-Watts of power. But today the power has been cut in half, we are transmitting with 1-Watt.
    We are testing the low power efficiency of broadcasting with the neutral injection method, which has been proven very effective in this installation.
    More test observations later.
    - March 27, 2012 at 2:28 pm #25462
      
      wdcx
      Total posts : 0
      So……..when driving around tell us about your range…
    - March 27, 2012 at 5:48 pm #25463
      
      Carl Blare
      Total posts : 0
      Headed east toward the same direction the electric lines from our transformer aim, and we have an interesting difference to note between 2-Watts and today’s power of 1-Watt.
      With 2-Watts the strong signal on 970kHz could be heard for 2.5 blocks before it dropped very rapidly into no signal.
      Now, with 1-Watt, the strong portion of the signal holds for 1.5 blocks, then there is a weaker signal but still receivable, until the 2.5 block point, when the signal disappears.
      I did another test using a portable radio, to see how well the signal does in the rear of the building, back where no electric lines are run from our particular transformer.
      There is one possible exception to the statement just made, the next house on the east is on the same transformer, and if they happen to have an electric line out to a backyard lamp post, that would make a difference. Due to a high fence I do not know what’s over there.
      The 970 signal became slightly weaker but was still very usable, up at the mulch pile, about 125-feet back.
      I believe we can safely return to a 2-Watt status, until the next test, when we will run 3-Watts.
    - March 27, 2012 at 8:23 pm #25464
      
      RFB
      Total posts : 0
      Take a portable and go to the 2.5 drop point, walk up to a power pole near that drop point and put the portable right up to the ground wire running down the pole. Should be able to pick up the signal, which verifies the signal is staying where it should be..on the wire traveling down the wire into every drop and into homes/businesses.
      If it is not detectable at that point, the 2.5 block drop point is where the grid separates onto another grid. A repeater or bypassing would be needed to continue on to the next grid and so on.
      RFB
    - March 29, 2012 at 2:07 pm #25472
      
      Carl Blare
      Total posts : 0
      While still transmitting at 970kHz we tried to up the power from 2 to 3-Watts, and the meters pinned and the AM band started chattering like a radiation detector. This was expected behavior and I’ll explain why.
      RFB had used his own LPB equipment to simulate my situation, he ran his “low band” transmitter at 970kHz (my frequency of choice) and found it could be done, if 5-Watts was not exceeded. What’s going on?
      Look at the LPB specs. The AM band is sliced into 3-parts, each requiring a different low pass filter in the output section:
      Low = 530-830 kHz
      Mid = 830-1270 kHz
      High = 1270-1710 kHz
      By running a low band transmitter in mid-band the filter is not correct and the transmitter becomes unstable above a certain level, in my case 3-Watts.
      Designing a mid-band filter is half explained by available LPB information, but there are some details that will need to be found in the absence of official information.
      To avoid stressing the transmitter I have moved to 670 kHz (low band) and am running at 3-Watts.
    - March 29, 2012 at 8:43 pm #25473
      
      RFB
      Total posts : 0
      More power will not get you any further range. Remember CC works by near field induction and not far field radiation.
      At most, with more power applied, what will happen is a much stronger near field and over-saturated receivers..not to mention exceeding the 157,000/F 15uV@30m specification. (221)
      Expecting results like that from a center point radiator such as a 3 meter antenna won’t happen. CC is a “wired” wireless form of radio transmission and our goal here is to keep the signal on the wire being coupled to. We want the signal to continue down the length of that wire for as far as it goes. Beyond that, requires another coupling point.
      Where your 3 meter antenna signal cannot penetrate, the CC system does by delivering the signal right into the power outlets. The signal need not even be a half watt ERP off that wire and still provide a clear signal at the furthest reaches of the wire’s length. What does emit off the wire must be limited to the specification called for in 15.221 and no further off that wire..ie distance from the wire, not down the length of the wire.
      As I pointed out, running the TX at 970 with a lower 3rd filter is tricky and should not be done at excess power levels, and is why your TX went into oscillations and spitting splatter everywhere.
      Reason why yours sputtered at 3 watts and mine didn’t even sweat at 5 watts plus is because of component tolerance between the two TX’s. at 10 watts my TX will sputter just like yours did at 3. Either case, both instances with both TX’s demonstrated the use of incorrect LPF, which creates an
      internal mismatch between the output toroid and the input of the LPF.
      It all makes for excellent self teaching lessons, and the adventure has barely begun!
      RFB
    - March 29, 2012 at 10:21 pm #25474
      
      Carl Blare
      Total posts : 0
      This morning at 8 the LPB was set at 670kHz, 3-Watts, with a VSWR of 1.5:1
      This afternoon at 5 it was checked and found to have changed on its own. The new power reading is 2-Watts. The VSWR remained at 1.5:1
      What is?
    - March 29, 2012 at 10:33 pm #25476
      
      RFB
      Total posts : 0
      The bias circuit in the final amplifier adjusts itself to surrounding temperature changes. Makes sense that at 8am when it’s cooler, the bias sets itself for that temperature range, then as the day goes on into the warmer temps of the afternoon, the bias will adjust itself and lower that voltage, in turn lowering the final amplification a bit.
      It’s working like it is supposed to, protecting that amp from over-heating.
      The time to worry is when it bounces from a setting of 2 or 3 watts and jumps out to 10 or more on its own..then there is a real problem to investigate and solve.
      Imagine what would happen if that amp did not have a temperature compensating bias. The amp would thermally run away and POOF..especially in an environment where air circulation lacks.
      RFB
    - March 30, 2012 at 2:08 pm #25484
      
      Carl Blare
      Total posts : 0
      Everything recommended by RFB has worked. Everything predicted by RFB has proven true. I believe this man should consider becoming the national carrier current consultant, and I very much believe that carrier current is a remarkable and fascinating mode of putting radio on the AM dial.
      This morning I set up on 570 kHz, first at 2 Watts. Then I checked every radio in the house especially to observe nearby stations at 550 and 590. I wanted to minimize the risk of covering either station, especially on cheap radios.
      By the time I had those two frequencies clear of interference, I was transmitting at 1/2 Watt, with a very low VSWR, just above 1:1
      Later we’ll do the drive bit to see how the range compares to the best of before, which was 2.5 blocks eastbound.
    - March 30, 2012 at 8:09 pm #25489
      
      Carl Blare
      Total posts : 0
      Took a ride with 570 playing on the dashboard, 1/2 Watt into the neutral carrier current system. Let me describe the result by listing comparative readings over the past several days on two different frequencies:
      1. 2-Watts at 970kHz has a strong signal on the auto radio for 2.5 blocks, then fades out fast;
      2. 1-Watt at 870 is strong for 1.5 blocks, then becomes weak but listenable for 1 more block, then gone;
      3. 1/2 Watt at 570kHz is exactly between the two results at 970. Not as strong as No. 1, but not as weak as No. 2.
      Of course the drive is right along the poles carrying the neutral wire up in the air, probably 40-feet from the car.
    - March 30, 2012 at 10:15 pm #25490
      
      RFB
      Total posts : 0
      Remember, that at the lower frequencies, it requires a bit more power to equal the same clear coverage range than what is necessary at the higher frequencies.
      Since your operating between two other stations, you were wise to ensure your CC signal was not over-lapping onto their channels by adjusting the power output level for adequate coverage. In fact, that is the exact procedure once a CC system is set up, to adjust the power level only to a point where good clean coverage is obtained.
      More power will not increase range, it will only increase the near field intensity and overload nearby receivers, and overlap co-channel stations.
      Your doing fine and doing all the right steps in your journey through the CC world.
      RFB
    - March 31, 2012 at 7:13 am #25491
      
      Ken Norris
      Total posts : 0
      Hi Carl,
      Your foray into CC is much appreciated. Wish I could find some gear I can afford.
      Block lengths vary from town to town. How long are yours? Can you give us a more accurate range?
      Can you find a frequency which won’t interfere so you can pump up the power?
      I would much like to try it here some day, but I get much more than 2.5 blocks (well, unless your blocks are very long) with a stick on my boat.
      If I didn’t have that advantage I’d try for the roof of a local hardware store, which is all metal, maybe 15000 sq. ft.
    - March 31, 2012 at 8:41 am #25492
      
      RFB
      Total posts : 0
      “I would much like to try it here some day, but I get much more than 2.5 blocks (well, unless your blocks are very long) with a stick on my boat.”
      Yes indeed! Neat thing about CC…if the frequency is open and even fairly clean of noise, Carl’s 2.5 blocks will be rock solid and potentially beyond 2.5 with a radio plugged into the AC power grid. Keep in mind his field tests were with a vehicle radio and it’s picking up the stronger inductive field (near field) up to the point of the change to the far field, and the signal drops…as it’s supposed to.
      Its a good chance that at the next nearest pole from the 2.5 block drop point, a decent portable held up to the utility pole’s ground wire, will pick up the signal and may pick it up within a foot or two before that.
      CC is an inductive system. At night when skywave slams 3 meter sticks, on dirt or water doesn’t matter, the CC system will transmit a strong clean clear signal.
      But the really neat thing with your situation Ken, is that you do indeed have one fine isolated Earth ground out there! Even for a CC system! You think that 3 meter stick on the boat does wonders…try a CC coupling netural with the return path being that same water ground system..lucky whale you! 😉
      RFB
    - March 31, 2012 at 2:19 pm #25493
      
      Carl Blare
      Total posts : 0
      The surveyors or architects who sketched this area decided that nothing would be rectangular or level. Every square inch is at an uphill/downhill angle, the streets are based on curves and triangles, and cross streets are either very close together or very far apart.
      When I did the comparative tests between the new AMT5000 and the original AMT3000 I used a measuring wheel to get accurate footage, but one day while I was skimming the sidewalk a town official drove past in his shiny black upscale car paid for with tax money, and he almost drove off the road when he saw that a civilian was doing something out of the ordinary. Before he could turn around and swing by again or call for back-up, I disappeared using a technique learned on the old “The Shadow” radio program.
      We are living in a time when even the smallest bureaucrat dreams of being the next Adolf. “If you see anything, say anything.”
      When RFB suggested I walk up to a pole and press a portable radio against the drop wire I could just hear the “neighborhood watch” ladies on their cell phones reporting to Homesick Security.
      How can a simple and honest street measurement be made? I have a plan. I am going to disguise the measuring device as a baby carriage or a dog-on-leash; an entire army could pass through the neighborhood if they used those two disguises.
    - March 31, 2012 at 5:23 pm #25494
      
      RFB
      Total posts : 0
      We are living in a time when even the smallest bureaucrat dreams of being the next Adolf. “If you see anything, say anything.”
      The result of SS Engineering, or Super Social Engineering. After 10 years of media pounding fear this, fear that, suspect this and suspect that, boogie man here, boogie man there and under your bed, is it any wonder why!
      Why should it be a shock that things are the way they are? Isn’t that what the public wants..rights stripped away and every individual is a potential terrorist?
      “How can a simple and honest street measurement be made? I have a plan. I am going to disguise the measuring device as a baby carriage or a dog-on-leash; an entire army could pass through the neighborhood if they used those two disguises.”
      NO..the baby carriage would still be searched, the dog on the leash would be considered as aiding and abetting, and the individual a re-incarnated Bin Laden.
      But hey..you still have your choice of being back scattered irradiated or groped and grabbed. Even little Jr will get his first wonderful exposure in front of hundreds of complete strangers.
      War on Tourism, War on Society, War on Freedom, War on Rights. And terrorism is the thing to be worrying about???
      Wait..be right back…my kitchen sink faucet is dripping one drop every 20 seconds. Better fix it before the green police show up and haul me off to some foreign land with no right to counsel or trial or even be charged with anything.
      Ain’t life grand!
      Pack lightly.
      RFB
    - March 31, 2012 at 6:08 pm #25495
      
      Carl Blare
      Total posts : 0
      I can’t pack lightly because the LPB2-20 Transmitter weighs about 50-pounds. I may have to stay behind. I won’t abandon it!
    - April 4, 2012 at 2:05 am #25513
      
      Carl Blare
      Total posts : 0
      At around 8 PM, now dark outside, I checked KDX CC, the name I will use for my carrier current station that is currently broadcasting at 2-Watts with no IDs, since the part 15 rules don’t require any. Everything was fine at 670kHz, the temporary frequency being used until I build a Low Pass Filter for the permanent home at 970kHz.
      One notch higher, 680, was completely blank, and another notch, 690kHz, the 1kW daytime power of the local station was now switched down to night power of 17.6-Watts, and it was coming in weakly, as usual for the low power.
      Going down a notch, 660kHz was blank, but something interesting happened on 650kHz. I was hearing WSM, Nashville, TN, 50kW, almost as clearly as if it were local. But I was ALSO hearing KDX CC at about the same level but with a very noticeable “echo” effect, as if it was a reflection being bounced back from down-line somewhere.
      I deliberately avoided being on 660, which otherwise would have been better than 670, because I didn’t want to crowd WSM. But now it appears I may be conflicting with them anyway and wonder what you all think or suggest about this observation (?)
    - April 4, 2012 at 7:34 pm #25516
      
      RFB
      Total posts : 0
      670 and 650 are 20Khz apart. And your wondering why your hearing a bit of the CC on 650 while operating on 670?
      The 690 signal, though local, is so weak there is no intermixing going on. Obviously the 650 blaring in at night is stronger so your going to hear some intermixing going on. However that is going to be highly localized and most likely only apparent within your location.
      I wouldn’t worry about it since your going to be operating on 970 in the long run. But if you are worried, then drop the power level to 1.5 or lower.
      RFB
January 30, 2012 at 9:08 pm #24439

RFB
Total posts : 0
That is a fairly quick delivery estimate. Should we all break out the party hats and noise makers in preparation to the anticipated post of “It’s here!!”? 🙂
RFB
January 31, 2012 at 2:35 am #24457

MICRO1700
Total posts : 0
Carl, one thing I missed was – is the
CC transmitter you are getting rigged
to transmit on the AM band out of the
box, or do you need a crystal for it?
If it does operate on a channel, is it
one that you have blank in your area?
Sorry, but I have looked back through the
notes and can’t find what you said about
this.
The economy in our house isn’t so great, but
I did a lot of laughing tonight
anyway – for no apparent reason.
My two favorite episodes of the old “Outer
Limits” series from 1963 both starred the
wonderful Robert Culp. They are “The Architects
Of Fear,” and “Demon With A Glass Hand.” The revival
series produced from 1995 to 2002 is very good, too.
Bruce, DOGRADIO STUDIO 2
- January 31, 2012 at 3:41 am #24460
  
  Carl Blare
  Total posts : 0
  I think there is infrequent mention of frequency in this… the frequency I thought I would use was 970kHz, but that would require changing parts in the output filter and the low band (550 – 830) is what the transmitter is wired for.
  I think Ultanium said he removed the crystal, but that’s o.k. because it was for 580 which I cannot use because of a full power station at 590.
  RFB taught me that a PLL Kit, which I have, can be used in place of a crystal and can be programmed with an on-board keyboard for any frequency.
  I’m going to start at 570kHz, hoping the Cuban Time Station doesn’t come in too strongly.
  By the way, you said you laughed for no apparent reason, well, I often laugh for reasons apparent only to me.
  RFB suggested a party to launch this CC station, so I ordered 20-cases of beer which we can enjoy while whipping the high voltage wires into the circuit breaker panel.
  - January 31, 2012 at 6:20 am #24461
    
    MICRO1700
    Total posts : 0
    That’s right. 580 was no good.
    I have seen some PLL kits on the
    net. I believe some of them can
    go from below 10 kHz to up to 70 MHz
    or so. I saw one that was a kit.
    It was not recommended for inexperienced
    kit builders.
    Did you have to build yours, or did it come
    assembled?
    I have heard that Cuban time station: Radio Reloj,
    on 570 and several other AM BCB channels.
    Well, good luck! And it really would be nice if
    we could all get together. It’s too bad we are
    all so far apart.
    Best Wishes,
    Bruce, DOGRADIO STUDIO 2
    - January 31, 2012 at 4:33 pm #24464
      
      RFB
      Total posts : 0
      “Did you have to build yours, or did it come
      assembled?”
      Here is the link to the PLL DataKit board:
      Datakit PLL Experimenter Board
      Very simple kit. If you can assemble a transmitter kit, you can assemble this little gem. And do not let the description put the boogie man fear in you. The kit itself, on a skill level chart compared to something like an AMT 5K, this kit would require a level 2 or 3 while the AMT5K would need a level 4 or higher.
      You have to build your own oscillator circuit, which there are example circuits within the manual/assembly instructions.
      And there is room on the kit board to permanently install an oscillator circuit, or two each capable of operating on different bands and selected by the use of a jumper. The PLL kit is only limited by your imagination for its uses.
      RFB
    - January 31, 2012 at 4:37 pm #24465
      
      kc8gpd
      Total posts : 0
      can you email me the manual?
      kc8gpd hotmail
    - January 31, 2012 at 5:14 pm #24466
      
      RFB
      Total posts : 0
      “can you email me the manual?”
      Sure..once I get my scanner to stop being stubborn. I was trying to scan the TCU-30 coupler manual for Carl and upon beginning the scan of the manual..the scanner starts acting up and locking up. I got it all apart on my bench, looks like it was just a tad dusty inside and collected lint and dust balls all over the guide tracks for the scanning bar.
      Good thing I am not an engineer! 😉
      RFB
    - January 31, 2012 at 5:46 pm #24467
      
      kc8gpd
      Total posts : 0
      when you get the tcu 30 scanned would like a copy of that (and schematic) as well.
      maybe i can home brew a coupler off of it.
      thanks,
    - January 31, 2012 at 5:58 pm #24468
      
      RFB
      Total posts : 0
      The TCU-30 manual I have does include the coupler schematic, parts list and mechanical diagrams along with interface instructions for both the transmitter and output connections to the electrical system.
      Tuning steps are also provided and I think there is even a couple of pages of flyers for other LPB products..though not very useful these days, it’s neat to see brochures on all the stuff LPB had in these manuals.
      RFB
    - January 31, 2012 at 5:58 pm #24469
      
      Carl Blare
      Total posts : 0
      It’s almost 11:56 AM CST and a check with the global tracking machine tells that Fedex left Earth City, Missouri, this morning at 8:56 with my 20-lb. load on board. I really made out like a bandit when it comes to weight gain… the money I spent weighed less than an ounce.
      Earth City is a name that ought to appeal to Bruce MICRO Dog 2 Studio Radio, the discoverer of the planet Phringus and its inter-planetary cargo conglomeration. Earth City may not have any residential units, unless somebody lives in a storage locker, as I believe it is an industrial park on the west side of the airport, right on the shore of the Missouri River.
      The carrier current carrier is on the way.
    - January 31, 2012 at 7:50 pm #24473
      
      RFB
      Total posts : 0
      Has it arrived yet? Is it there yet? Is it hooked up yet?
      Has it arrived yet? Is it there yet? Is it hooked up yet?
      Has it arrived yet? Is it there yet? Is it hooked up yet?
      😀
      RFB
    - January 31, 2012 at 7:57 pm #24474
      
      Carl Blare
      Total posts : 0
      Having left Earth City at 8:56 AM and now it’s 1:56 PM here, miles to the southeast from there, nothing yet.
      But while we’re waiting, there is ANOTHER QUESTION, if you can believe that.
      Is it possible to put more than one carrier current station from the same location?
      What are the ways of doing it?
    - January 31, 2012 at 9:04 pm #24479
      
      Carl Blare
      Total posts : 0
      2:59 PM Truck arrived. Man delivers big box. Carl Blare has door already open. Box is now sitting unopened on the office chair.
      What should I do?
    - January 31, 2012 at 9:14 pm #24481
      
      RFB
      Total posts : 0
      “Box is now sitting unopened on the office chair.
      What should I do?”
      STOP! Take a deep breath. Calm down. Relax. Savor the moment. Take a picture. Run outside and yell “It’s HERE!” 😀
      Now go hook that thing up and get on the air! 😉
      RFB
    - January 31, 2012 at 9:48 pm #24490
      
      Carl Blare
      Total posts : 0
      Using surgical skills learned on the internet I opened the carton, spent 2-hours removing radioactive packing peanuts that seemed to like my hands and didn’t want to go in the waste basket, and found the following contents:
      1 – LPB2-20 Transmitter
      1 – Radio Systems CP-15 Coupler
      Upon careful inspection of both units, I have reached the conclusion they are real.
      There will be a long pause while I actually assemble the PLL Circuit Card.
    - January 31, 2012 at 9:59 pm #24492
      
      RFB
      Total posts : 0
      Those darn tapes…err peanuts! 😉
      They do get in the way don’t they! At least they stuck to your hand and didn’t end up all over the floor from a light breeze!
      They tend to fly really well with a very light wind! Put’s a shame to the card game “52 pickup”!
      RFB
    - January 31, 2012 at 11:23 pm #24503
      
      RFB
      Total posts : 0
      “There will be a long pause while I actually assemble the PLL Circuit Card.”
      Remember that for simplicity and less issues with stray capacitance and inductive effects, build the oscillator to work ‘on frequency’ instead of one that will be 6 times the operating frequency.
      It’s a lot easier to build an oscillator that runs at 1Mhz than it is to build one that needs to run at 6 times that frequency. But the choice is yours.
      If you build a simple LC network to replace the crystal, you will need to leave A2 in place as well as A3 in place. The LC network, controlled by the PLL, will have to be the circuit that operates the oscillator inside the A2 IC. It is then divided by A3 down to the intended operating frequency in the MW band.
      If you build an actual oscillator at 6x the frequency, you wont need A2 as A2 is simply an oscillator throwing square waveforms. Your new oscillator operating at 6x frequency merely needs to feed into A3 for division down to the MW frequency.
      If you build an oscillator operating in the MW band, you wont need A2 or A3 at all. Simply inject the oscillator signal onto A3 socket pin 8, or at the “FRQ TP” stud on the exciter board. Follow the oscillator with a good buffer stage for isolation, and after that a good gain amplifier to ensure good drive signal for the balanced modulator IC.
      You can even make the oscillator output variable for fine adjustment of the drive level prior to the modulator to peak the modulator’s performance and prevent over driving which will cause RF waveform distortion and clipping.
      The adventure is just beginning!
      RFB
    - February 1, 2012 at 12:04 am #24505
      
      Carl Blare
      Total posts : 0
      I am off course in my thinking. If the LPB2-20 operates from a crystal, is that not therefore an oscillator by definition?
      If the PLL circuit generates the frequency in place of a crystal, is that not the same as having a crystal?
      If the transmitter needs an oscillator with the PLL card but doesn’t need one with a crystal, that seems odd.
      How can I get straight on this?
    - February 1, 2012 at 1:36 am #24508
      
      RFB
      Total posts : 0
      “If the LPB2-20 operates from a crystal, is that not therefore an oscillator by definition?”
      No. A crystal is not an oscillator. A crystal is a PART of the oscillator which makes the oscillator work. Without it, the oscillator would need an LC circuit to form the resonant tank and feedback to attain oscillation.
      The PLL..as stated on it’s own manual and website and here, does not have an oscillator. You have to add that yourself. The PLL cannot directly replace the crystal without building a replacement for the crystal itself..ie the LC tank circuit.
      You can build an LC circuit to replace the function of the crystal and have the LC circuit controlled by the PLL via a varactor diode within the LC circuit. With this approach, you continue to use the oscillator circuit inside the A2 IC chip.
      The PLL does not generate it’s own frequency..that is why you have to add an oscillator and is why oscillator circuits are contained within the assembly manual. Without the oscillator, the PLL can do nothing on its own. The PLL can be used to control other oscillators. But all the same, the PLL board needs an oscillator to control. It can also control an LC network via a varactor diode which in turn makes an oscillator function, thus controlling the oscillator frequency.
      I think your confusion is coming from thinking this PLL board is a direct replacement to the crystal. It is not.
      You need something to make either the internal oscillator in the transmitter (A2) to work, such as a crystal or an LC tank circuit. The crystal merely sets the frequency to one frequency and keeps it there. An LC tank allows you to set up the oscillator in the IC A2 to be variable, by means of a tuning cap or inductor, or by control through a varactor diode getting a phase lock from that PLL board.
      Either way you look at it, the transmitter needs an oscillator regardless if that oscillator is controlled by that crystal, or an LC tank controlled by the PLL, or an external oscillator controlled by the PLL.
      Remember, the PLL board is NOT an oscillator! You have to add that, or make an LC tank circuit to replace the crystal directly and the PLL controls the LC tank circuit via a varactor.
      RFB
    - February 1, 2012 at 1:40 am #24509
      
      Carl Blare
      Total posts : 0
      There is an oscillator within the Big Talker shortwave transmitter. Will that one do the job?
      http://www.kdxradio.com/bigtalker.html
    - February 1, 2012 at 2:16 am #24510
      
      RFB
      Total posts : 0
      The oscillator in that version of the Big Talker can work providing you build an LC tank circuit to replace the crystal and re-arrange it’s design a little. It is designed to work around a crystal so the circuit will need to change a little to work off an LC tank.
      If that oscillator can go up as far as 1.7Mhz then your good.
      Take a look HERE for an idea of a crystal equivalent circuit.
      And HERE are some pictures of a wide variety of LC tank circuit equivalents to crystals.
      For an even easier example..look at this schematic of a tunable phonograph oscillator circuit. Install a varactor diode at the junction of the inductor and the 33pf cap, and then on to the PLL control voltage lead. Sampling for the PLL can be picked up after the buffer stage.
      I recommend you read through this also:
      VCO and PLL Oscillator Tutorial
      RFB
    - February 1, 2012 at 8:57 pm #24527
      
      Carl Blare
      Total posts : 0
      While waiting for the next thing to happen, whatever that is, I came up with another brilliant question to ask:
      WHAT IF one carrier current station were coupled to the mains in the conventional way, i.e., the 2-hots & neutral,”
      AND another carrier current station were coupled to the neutral line???
      Those two loads would be feeding different parts of the electrical system, so they wouldn’t collide with each other.
      Of course the two stations would be on different frequencies?
      Did I just invent something?
    - February 2, 2012 at 12:00 am #24528
      
      RFB
      Total posts : 0
      Well in such a configuration, one coupler would be using the neutral of the AC as it’s return path, while the other would be using that same neutral of the AC as the injection path, resulting in the 2nd coupler dumping all it’s signal right into the return path of the first coupler, and potentially burning up the output toroid, or at the very least over-saturate it to the point it could damage either or both transmitters and couplers.
      What is still needed is a way to isolate the two from each other, while allowing each coupler the ability to see the load paths properly onto themselves, and keep them from shoving signal into each other. It would still require a combiner.
      But an interesting idea for sure.
      RFB
    - February 2, 2012 at 1:19 am #24529
      
      Carl Blare
      Total posts : 0
      Rather than modify the LPB2-20 Transmitter by designing an oscillator circuit/PLL combination to excite the unit, I have decided to preserve the design as originally intended, especially when finding that the needed crystal is reasonably priced.
      Source; International Crystal Manufacturing
      http://www.icmfg.com
      The PLL circuit we purchased will not go to waste. It will remain attached to the original project for which it was obtained, the Deep Voice LowFER Deep Voice Transmitter, now under development here on this website.
      Estimated shipment date is Feb. 22, so this thread will just be dangling around in the meantime.
    - February 2, 2012 at 1:50 am #24530
      
      RFB
      Total posts : 0
      Well hopefully the crystal you get will be a good frequency to work. Although 1 crystal is not that big of a deal as far as expense, several of them would be, and having just 1 crystal may not be the correct one to work if the frequency chosen doesn’t pan out to be workable.
      This is why the suggestion of the PLL would be the way to go during the testing phases.
      You wont have to modify a thing on that transmitter to use the PLL board. Removing the two IC’s and injecting the frequency at the frequency test point or pin 8 of A3’s socket isn’t exactly modifying the transmitter itself. It is merely substituting the A2 and A3 chips plus the crystal.
      When the good frequency is found, simply order a crystal for that frequency, reinstall A2 and A3, install the new crystal and bada bing!
      Hopefully the one you already ordered and its final frequency will be workable for your new CC station!
      RFB
    - February 2, 2012 at 2:05 am #24531
      
      Carl Blare
      Total posts : 0
      I ordered crystals for 530 and 570. I am beginning by using the low band, because using any frequency above 830kHz would require a real serious modification of the output filter, and I see those big toroids and realize I am not sure how to design the correct toroids for the mid-band.
      Also, looking at the PLL literature that came with the kit, it is all over the place as far as writing is concerned, and does not come through clearly to me. On top of all that, designing an oscillator appropriate to the low AM band is not something my skills have ever dealt with, and at this exact moment I would prefer to postpone a college course until months later.
      On the long slow road it would be nice to try the PLL method, and as of now the LowFER transmitter will be the time and place for that.
      I am going to run initial tests at 530kHz which is sort of off-band and won’t capture much attention. When the result is fine-tuned, I’ll move it to 570kHz and call it a win.
      If it works poorly I’ll be frustrated, but may never try the mid-band, because for all the trouble there is no guarantee it will work better.
      Subject to change.
    - January 31, 2012 at 9:15 pm #24480
      
      RFB
      Total posts : 0
      “Is it possible to put more than one carrier current station from the same location? What are the ways of doing it?”
      Not without the use of a combiner to isolate each station’s coupler output to the common loading point..in this case the power “hots” or the neutral.
      It’s the same approach when combining transmitters to use a common “community” transmitting antenna system. The combiner isolates, protects and makes sure each transmitter, or in this case the combiners, see the load properly and not get interference from the other, or cause interference to the other.
      As far as I know, LPB never made any sort of combiner for CC systems. But there is a little known trick that some CC stations did use to combine the couplers. LPB made power splitters and these worked great as basic combiners, after a little bit of modification. They are the same combiner toroid assemblies used in the combination transmitters which made their 60 and up higher powered transmitters.
      Not sure you want to venture into that just yet. Finding those combiner toroid assemblies and power splitters is even more difficult than finding the deals on transmitters and couplers. But perhaps one will show up soon.
      Patience pays. 😉
      RFB
February 2, 2012 at 2:14 am #24532

MICRO1700
Total posts : 0
As you guys know, I have been waiting for a CC
transmitter that belongs to me – a good friend
has it. This guy is great and I’ve known him for
decades. But he is going through a lot right now.
And he lives in another state.
The reality is I may not see this transmitter for a
long time. But I do believe I will eventually get it back.
However, in getting ready for it, like Carl, I have thought
about different frequencies on the AM BCB where i
can eventually transmit. This is an old LPB tube CC rig,
that uses fundamental crystals. There is an inexpensive
source for AM BCB crystals above 1000 kHz so operating
about there would not be a problem.
However, if I decide to go lower in the band – I am stumped.
Do any of you guys know of a manufacturer that will
make a crystal for below 1000 kHz that can withstand
the energy that a tube oscillator would put through it?
I’m not really in any condition to build an crystal oscillator that runs
on a multiple of the frequency which is divided down to the
actual AM BCB channel. At least not right now.
As always, thank you!
Bruce, DOGRADIO STUDIO 2
- February 2, 2012 at 2:49 am #24533
  
  Carl Blare
  Total posts : 0
  Hello Bruce:
  The people at ICM, International Crystal Manufacturing, have always been very wonderful to talk with. Today I talked with a guy, and although I only ordered two crystals, he spent a calm time talking to me in depth about the subject of crystals.
  He is Mark Handley, his number is 800-725-1426 Ext. 265
  ICM is familiar with LPB transmitters because they were the OEM supplier for LPB. They may have the exact crystal you need.
  - February 2, 2012 at 3:08 am #24534
    
    MICRO1700
    Total posts : 0
    Good To Hear From You As Usual!
    OK. When I eventually get the transmitter
    back, I will call that number.
    Thanks very much Carl!
    Bruce< DOGRADIO STUDIO 2
    - February 2, 2012 at 8:35 pm #24541
      
      RFB
      Total posts : 0
      Those crystals aren’t cheap. But modifying the oscillator to run an LC varactor circuit controlled by a PLL is not that difficult.
      I posted some links to excellent reference material on LC and VCO circuits. Those references refer to solid state designs however.
      But with a little bit more research..like examining other tube based oscillator circuits, it won’t be impossible to convert that RC-6 to work with a PLL.
      In fact just recently, a Cunningham 10 watt transmitter was sold on ebay that was modified with a PLL board, replacing the entire oscillator sections. PLL Cunningham
      Take a look at the pictures of the unit. You can clearly see the PLL board in place of the oscillator tube section prior to the final tube.
      RFB
    - February 3, 2012 at 3:19 am #24561
      
      MICRO1700
      Total posts : 0
      Gee RFB, that thing looks really great!
      I guess I’ll look at E-Bay if I get some funds.
      I’m going to stop bothering my friend for a
      while. If he can’t send the RC-6A to me now, I know
      there is a good reason. He is very reliable and
      sincere.
      In the meantime, I’ll just keep learning about this stuff.
      Thanks again for the info.
      Best Wishes,
      Bruce, DOGRADIO STUDIO 2
    - February 3, 2012 at 4:49 am #24562
      
      RFB
      Total posts : 0
      I wish I had the funds to grab that unit during that auction. But every now and then good stuff like that shows up.
      My luck its always good deals show up but no funds and when funds are handy, no good deals to be found! Ironic it works out like that a lot! But the patience pays off eventually as Carl discovered. Miracles do happen and when least expected.
      With the way things are out there I am sure your friend is pretty tied up just trying to make ends meet. He will get that sent back to you soon. 🙂
      RFB
February 3, 2012 at 7:30 pm #24567

Carl Blare
Total posts : 0
Evidently there is more than one reality.
The one in here, inside the internet building, brings an image signal from AM 1430 while listening to 530 kHz. Since it was “only an image” and therefore not a genuine station, I ordered a 530kHz crystal for carrier current.
But out driving around in the car, that reality has an entirely different 530kHz, one where the Illinois Department of Transportation comes in with a muffled voice giving constructions zones. Although Illinois is 8-miles from here, I have officially abandoned any plans to use 530kHz.
ICM, International Crystal Manufacturing, was very generous and allowed me to change the order to a 670kHz crystal, still within the AM low band.
- February 7, 2012 at 10:56 pm #24635
  
  Carl Blare
  Total posts : 0
  Continuing my last post, I am beginning to have a grasp of what separates reality # 1 from reality # 2. It is the walls of the house.
  If you are inside the walls, that’s #1, and outdoors is #2. Why are they so different? It has to do with dB. DeciBels. What are those? Well, one way of describing them is that they are a difference of attenuation.
  Huh?
  I think RFB will be proud of me, but I now see that out in the car the world is louder, the radio more sensitive, because the walls of the house are gone and are not causing a loss of signal strength coming from all the radio stations. After all, no licensed radio station puts its tower indoors. There is a good reason for that.
  Stop. Now we face up to Reality # 3. And that is that no single web posting should go on for too many paragraphs. So I know that I should stop now, and continue this on a future posting. Meet me there.
  - February 7, 2012 at 11:03 pm #24636
    
    RFB
    Total posts : 0
    Isn’t being both the teacher and the student fun?!!
    I may have to retire early if you keep turning in these excellent thesis posts! 😉
    RFB
    - February 8, 2012 at 12:46 am #24638
      
      Carl Blare
      Total posts : 0
      Teacher and student?
      Who?
      You or me?
      Both?
      What have I taught you?
      You sure teach me plenty. That’s for sure. Why, if I was paying for all this advice it would be too costly. Or would it?
    - February 8, 2012 at 1:01 am #24639
      
      RFB
      Total posts : 0
      Everyone can be their own teacher as well as their own student.
      A good example…when your AMT5K unit arrived. Before breaking out the solder and iron and clippers and screwdriver…you studied the assembly manual to become familiar with the unit’s circuitry and theory of operation, identified all the parts and inventoried them, then after all that and once you felt confident enough to proceed with the assembly, began doing just that knowing which way the cathodes of diodes and polarity of electrolytic caps and orientation of DIP IC’s and FET’s were to be mounted onto the PC board.
      You were in effect a teacher and a student.
      We all are a teacher and student at some point..no matter what it is we are dealing with…assembling kits, reading information in a book or on the web, or just walking down the street and being aware of what is all around us on a daily basis.
      If we were all to just close our minds and never explore or discover and totally depend on something or someone to tell us how to all the time…we would be nothing more than automatons and zombies requiring a punch card program to set our zero’s and one’s.
      Costly? That would depend on a lot of things. But in my view, information is meant to be shared. Knowledge is meant to be spread everywhere and to everyone. To me knowledge is like air, everywhere and available for everyone to take in and continue life.
      It is the stingy, the greedy, the selfish, the power hungry that hoard knowledge for themselves because they believe in that other meaning of “Knowledge Is Power”..that other meaning is taken as know more than the other so you have an advantage over them, which is a sick and twisted definition to those three words.
      RFB
    - February 8, 2012 at 2:39 am #24645
      
      Carl Blare
      Total posts : 0
      I must say I agree that knowledge belongs to the public domain.
      The idea of private knowledge seems anti-social.
    - February 8, 2012 at 4:21 pm #24652
      
      Carl Blare
      Total posts : 0
      From inside the house 570 and 970 seem like good carrier current frequencies because they are mostly blank all the time.
      Outside driving around in the car there is no such thing as a blank frequency. There are stations on every channel.
      Aha, but the strength of carrier current is that it delivers the signal right into people’s homes via the power wires, thereby by-passing all that outdoor band clutter.
      Home run and touchdown!
    - February 8, 2012 at 4:39 pm #24653
      
      RFB
      Total posts : 0
      “Aha, but the strength of carrier current is that it delivers the signal right into people’s homes via the power wires, thereby by-passing all that outdoor band clutter.
      Home run and touchdown!”
      Woah hold on there before starting that play. Let’s take a closer look at this situation.
      You are correct, the CC signal will be delivered directly to homes and businesses via the power lines and right up to their wiring in the home or building. And yes the CC signal will be like as if their radios are in the same room as your TX is.
      However, you have to remember that their radios still have that internal ferrite bar antenna and still picks up over the air signals at the same time your signal is present on the AC wiring. It is that very reason why you have to be very careful in choosing a frequency. There could be someone who may listen to a station on one of those frequencies and has set up an elaborate antenna or even a simple long wire to pull those stations out from the clutter.
      This could be a problem for both that person and your CC operations. Remember what I was pointing out about choosing a frequency in CC. That preventing interference is even more crucial than that of a simple wire antenna setup or 3 meter antenna setup. Because your signal has a better chance of penetrating into homes than would the short wire or 3 meter antenna, you could cause interference even more with a CC system.
      Also keep in mind about the potential for inductive interference to telco and cable systems. There are frequencies in the MW band that may cause the inductive interference more than other frequencies. For example, the frequency 570 might not cause much interference at all to other services, but 970 might. Or it could be the other way around, 970 causes inductive interference while 570 does not.
      As I pointed out also..CC is a “flux science”. And you can sit with calculations all day long and apply something from those figures to the real world and discover a whole different result. CC is a bit tricky..sometimes stubborn.
      But don’t be discouraged by all of that. It is all a part of learning what will work and what won’t work. And is why I suggested the PLL route instead of crystals to begin the testing. After a couple of crystal purchases the expense begins to add up..and that of course will give reason to become discouraged.
      Just keep these things in mind when doing your open frequency testing. Never leave any stone unturned.
      RFB
    - February 8, 2012 at 5:52 pm #24655
      
      Carl Blare
      Total posts : 0
      Got it couch!
      That’s why I’m declaring this National PLL Week. This week everyone on the team will become proficient with PLL applied to radio transmission.
      No broadcaster will be left behind.
    - February 9, 2012 at 1:12 pm #24675
      
      RFB
      Total posts : 0
      Class……Class……….Class…………SHADDDDUUUPPP!!!
      Thank you.
      (from a Cheech and Chong “Class Teacher” comedy skit)
      Ok instead of building a variable oscillator from scratch and because my parts bin is somewhat empty, why not take a known working design and modify it slightly to be PLL controlled!
      The following modified oscillator is based on Wenzel’s “phono2” variable oscillator…found HERE. The original design is 2/3 way down the page.
      I have built this “phono2” circuit a couple of years ago prior to replacing the exciter board in my LPB TX 2-20 unit with the C.Cuff C-QUAM board. It was during my testing to find a suitable frequency and since I did not want to spend money on crystals, this was the way to go and it works great.
      And HERE is the modified design schematic with component values..including part number for the varactor diode.
      Use a 9 volt regulator tapping the 15VDC rail in the TX for this oscillator’s power supply.
      The inductor coil is a salvaged local oscillator coil from a non-working AM radio. The coil winding to use is the hi-side, or higher resistance side. Leave the other pins unconnected. For added stability, ground the metal case of the inductor to circuit ground.
      Tune the inductor so that the oscillator is operating close to the desired locking frequency. Then enter the frequency code into the PLL and the oscillator will lock.
      In Wenzel’s design and intent, his circuit was designed to accept audio modulation at the base. Since we do not need the oscillator modulated, the adjustment for audio and input for audio part of the circuit has been removed.
      Once the desired operating frequency is entered into the PLL keypad, the oscillator may jitter before locking. Simply tune the inductor very slowly until the oscillator locks and the jitter stops.
      The output of this circuit feeds pin 8 of A3’s socket, or the frequency test point slug on the exciter. The oscillator puts out a relatively low signal level but adequate enough to drive the balanced modulator and exciter amplifier to produce enough final power of about 8 watts, plenty for the purposes of frequency hunting.
      Now..get busy! :p
      RFB
    - February 9, 2012 at 11:24 pm #24684
      
      Carl Blare
      Total posts : 0
      Thank you RFB for this tutorial, the idea behind the PLL is coming clearer the more I avoid doing anything about it.
      So, I have printed your instructions and the circuit, and am getting to work.
      Here are some early questions…….
      I do not have a non-working AM radio to scavenge a local oscillator coil, but I think that’s a catalog item….
      There are two items described as 1uH, but they are drawn with different symbols, so could you please give a description of how they differ?
      “The oscillator puts out a relatively low signal level…” Can that be improved by not using resistor 2.2k ?
      Will PN2222A work in place of 2N4401 ?
      RELATED QUESTIONS
      This is a carrier current thread, but we are also considering the PLL over on the long wave project, so here are two questions about that:
      Will this same oscillator work for long wave?
      Will the PLL keyboard somehow allow using 162kHz?
    - February 10, 2012 at 11:10 am #24685
      
      RFB
      Total posts : 0
      Re-load the image for the modified schematic..I left out one component between the varactor and inductor. Everything else is the same.
      Answers in order of questions in post:
      “I do not have a non-working AM radio to scavenge a local oscillator coil, but I think that’s a catalog item”
      Yes. These can be ordered at Jameco or Digi-Key. Simply search for “AM Local Oscillator coil”. See HERE.
      “There are two items described as 1uH, but they are drawn with different symbols, so could you please give a description of how they differ?”
      The reason for their difference in the drawing is because there was no room to draw a curly coil in the space where the square is drawn. The value is the same..1uH, what is referred to as a “molded choke”.
      “The oscillator puts out a relatively low signal level… Can that be improved by not using resistor 2.2k?”
      The 2.2k resistor provides some padding between the oscillator output and load. Removing it would also remove that padding and isolation from the oscillator, and more than likely will prevent it from oscillating correctly. Leave the 2.2k resistor in circuit!! If you want to increase the oscillator output level, add a simple buffer amplifier stage. I will draw up one shortly and post as an addition within this post later.
      “Will PN2222A work in place of 2N4401?”
      You can look up the specifications for each transistor and note their maximum and minimum voltage ratings and operational ranges as far as gain and frequency. Since that Wenzel oscillator was designed around the 4401 and the working voltage of 9VDC and inductor values (not the variable), swapping out with a 2222A may have some issues such as unstable oscillation and/or multiple oscillations across the transistors frequency curve. In other words, the oscillator may not oscillate at a single frequency, but dozens and appear like the teeth of a saw on the spectrum analyzer. It’s best to use what the circuit design calls for..the 4401. But feel free to try a 2222A. At 9VDC with uA for current draw, nothing will blow up in your face. 😀 The worst that could happen is the oscillator simply doesn’t oscillate or as described…oscillates unstable.
      “Will this same oscillator work for long wave?”
      Not with the part values listed, which is for the MW band. But the basic design of the circuit can be used for LW frequencies. Things like the LC tank, the feedback loop and coupling component values will have to change for the lower frequencies. The same transistor can be used.
      “Will the PLL keyboard somehow allow using 162kHz?”
      Yes. Punch in 000016, and after the LED flashes indicating it took the entery, use the up key to step up to 162. The manual says 10khz steps, but it is really 1khz steps.
      Buffer stage:
      HERE is a schematic for a simple one transistor buffer stage with parts list. Sourced from HERE.
      RFB
    - February 10, 2012 at 5:39 pm #24691
      
      Carl Blare
      Total posts : 0
      Thank you for the clarifications.
      In the last post RFB wrote:
      “Re-load the image for the modified schematic..I left out one component between the varactor and inductor. Everything else is the same.”
      I re-loaded the image for the modified schematic and it was identical to the previous image I had printed. I think perhaps the first time I downloaded the image it had already been up-dated. Just to make sure, tell me which part had been excluded from the first image posting.
    - February 10, 2012 at 8:55 pm #24693
      
      RFB
      Total posts : 0
      The correct schematic will have a 10pf capacitor between the varactor diode’s cathode and the variable inductor coil, right after the 1uH “square” choke.
      RFB
    - February 10, 2012 at 10:24 pm #24696
      
      Carl Blare
      Total posts : 0
      I am now certifiable and have completed this phase of the PLL education.
      I have no more questions at this time, a very rare event, possibly mistaken.
      Probably there is a question I should have, but what would it be?
    - February 10, 2012 at 11:18 pm #24698
      
      RFB
      Total posts : 0
      “Probably there is a question I should have, but what would it be?”
      Without questions, there can be no answers. Without answers, there can be no progress.
      The first step to wisdom is “I do not know”.
      The first step to knowledge is asking. 🙂
      RFB
    - February 12, 2012 at 9:49 pm #24711
      
      MICRO1700
      Total posts : 0
      My friend in New Jersey has been able
      to look at it on the bench. He has
      taken some measurements and will probably
      have some recommendations. So now it’s
      in the pipe, so to speak.
      He says he will have it in the mail after
      he does the evaluation.
      So, this is starting to move.
      We’ll see what happens.
      Best Wishes,
      Bruce, DOGRADIO STUDIO 2
    - February 12, 2012 at 9:55 pm #24712
      
      Carl Blare
      Total posts : 0
      That is good news, DOG 2, when you get the unit working will you be trying carrier current?
    - February 13, 2012 at 2:43 am #24716
      
      MICRO1700
      Total posts : 0
      First of all, the transmitter
      cannot be on 860 kHz. (This is
      where it is now.) So that will
      have to be changed. I will at
      least have to get 3 new 6AL11 tubes.
      That is what the unit needs.
      I had made a coupler before for my
      Panaxis transmitter. (I no longer have the
      Panaxis.) It WAS actually a big loop receiving
      antenna for the AM BCB. I cut into the loop
      so that it became a big LC on the output of
      the Panaxis. Then I wound the AC cord
      around the loop, which was feeding the
      Panaxis. After that I plugged the AC cord
      into the wall, got the carrier on the radio,
      and tuned the loop for max signal.
      So, I plan to do the same with the RC-6A,
      except the 6 watt signal will be attenuated
      to a watt or two. That way the transmitter
      will see a load from the attenuator that
      is not too far off the mark. Then I will
      take the RF energy from the output of the
      attenuator and feed it to the homemade
      coupler. Whether or not it will really work
      remains to be seen. But I want to try it before
      I try anything else because it is easy.
      By the way, I plan to ground the transmitter itself
      to a water pipe, but my plan is to not ground the
      AC cord. It will be connected at hot and neutral,
      but not at ground.
      That’s the only idea I have now. It may be possible to
      get a real coupler from my engineering friend here
      in Connecticut, but I want to try this idea first.
      Beggars can’t be choosers. I know now that the RC-6A
      is in the pipeline. So now, we’ll just wait.
      Best Wishes,
      Bruce DOGGRADIO STUDIO 2
    - February 13, 2012 at 3:18 am #24717
      
      Carl Blare
      Total posts : 0
      We already know you will report the results of your plan, and it will be interesting to learn from it.
      If RFB is tuned in, maybe we can get an estimate of what might happen with your approach, Dog 2.
    - February 13, 2012 at 5:10 am #24718
      
      RFB
      Total posts : 0
      “If RFB is tuned in, maybe we can get an estimate of what might happen with your approach, Dog 2.”
      Well that big AM receiver loop with the power cord wrapped around it is basically the same thing you will find in your TCU-30 coupler…a toroid transformer…minus the ferrite core.
      A large air toroid transformer with primary side tuning (TX match) and a non-tuned secondary (power cord), which depending upon the number of turns of power cord around the split AM loop antenna, determines the inductance of that secondary as well as coupling efficient. It also provides the isolation from the voltage potentials on the AC power side.
      Although more turns of power cord around the big AM loop antenna will increase the coupling factor, it will also increase the amount of effect from power line inductance fluctuations from the varying load conditions of the power lines/wiring on the big AM loop antenna, in turn shifting it’s inductance and in turn changing loading on the TX.
      Also there will be a fair amount of signal radiating directly off the big air toroid coupler degrading CC performance.
      It will basically be a dual function radiator/coupler system.
      RFB
    - February 13, 2012 at 6:09 am #24719
      
      MICRO1700
      Total posts : 0
      Well, if it’s going to be a combination
      radiator/coupler – then I guess it’s a
      good thing it will be in the cellar!
      There’s still quite a while to wait.
      I don’t like illegal stuff, so if the
      field strength is too much, I won’t
      continue the experiment.
      I’ll let you guys know every step of
      the way, when it comes. I hope it’s
      pretty soon.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - February 13, 2012 at 2:49 pm #24720
      
      RFB
      Total posts : 0
      “I don’t like illegal stuff, so if the
      field strength is too much, I won’t
      continue the experiment.”
      Well so far and up to this point, your “Big Loop Coupler” has gone no further than a quick description of it and pointing out that it is an experiment. And at this point…there is still plenty of room for more theory.
      In your experimenting, try shielding the loop, if possible by placing it into a large cardboard box that is wrapped up with conductive material..like a thin metal mesh such as chicken wire fencing or aluminum foil. Ground the mesh or foil to the same ground path of the TX. This will form the same type of enclosure as the TCU coupler, and keep any RF energy emitted off the big coupler inside the box.
      It’s not pure 100 percent nth decimal point number crunched created catastrophe but it shows and demonstrates…if being inspected…that it is an experimental device with steps taken to prevent operation outside of it’s intent.
      And as you go along and refine The Big Loop Coupler, eventually it will get to the point of going beyond the experimental stage and turn into a practical application device. Then a “Big Looper Coupler V2” will come about down the road as more ideas begin to form while the first one is in use…and so on.
      Who knows, you may be on to creating a brand new Part 15 CC coupling system, eventually sizing it down too. But until that first step is taken, by experimentation and trial and error and yes if so desired..crunch numbers for a few hours, none of it will ever happen.
      Don’t fear experimentation and discovery..the tinkerer boogie man fears what you will discover because it is experimentation and discovery is what will refine your coupler and make it work better..and put the tinkerer boogie man where he belongs…somewhere else instead of getting in your way.
      RFB
February 13, 2012 at 8:45 pm #24727

MICRO1700
Total posts : 0
I have a bunch of interesting odds
and ends to tell you and the group,
but right now this message will have to be
short.
Thank you for the shielding idea.
I will do that if this thing starts
to go anywhere.
Funny thing, I was thinking of putting
it into a metal trash can, but I don’t
even know if they make those anymore!
Well, now that my friend has this thing
on his bench, we’ll wait and see what
he has to say about it’s condition.
Thanks again!
Bruce, DOGGRADIO STUDIO 2
- February 14, 2012 at 11:02 am #24743
  
  RFB
  Total posts : 0
  That’s good to hear the RC-6 is on the bench and being checked for you Bruce! Won’t be long now!
  RFB
February 14, 2012 at 11:59 pm #24754

MICRO1700
Total posts : 0
I was beginning to stop thinking about it,
because my friend hadn’t said anything,
and I know that if he can’t do something,
there is a good reason.
That’s why it’s so funny that as soon as I
put it out of my mind, he was able to get
to look at it.
As a ham, you might of heard of the AF4K website.
There is a lot there – but this guy, AF4K sells crystals
and other things. I believe the crystals are heavy
duty. He has a bunch for 1 MHz and above, and
a lot for the upper end of the AM BCB.
(I know there are other ways to get this unit to work,
but I have always been intrigued by his collection of crystals.)
He had a crystal for 535 KHz before (It’s gone now) and
I thought – what a weird frequency to test on. Only
analog radios would be able to get the transmission.
(These rocks are inexpensive, by the way.)
Anyway, the 535 made me think of some of the AM dxing
I used to do on the low end of the AM BCB. I heard stations
on 535, 545, and 555 kHz. I don’t remember what the 535
and 545 were, but the 555 is still on the air. St. Kitts, I
believe, and – late at night – they rebroadcast the BBC. I
understand they are the last split channel transmitter left
in the Caribbean.
In French Guiana, there was a really cool station on 1375 kHz.
It’s been off the air for years, but I used to listen to it in the
wintertime. I think it was 10 kW, and they played all kinds
of cool rock and blues, in the French language. I really miss
that one. I was a good propagation indicator. And I liked
their programming.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- February 16, 2012 at 9:10 am #24785
  
  RFB
  Total posts : 0
  Those Khz fundamentals are quite pricey. They were even back in the hey day. Sometimes even those crystals show up on ebay now and then.
  RFB
  - February 17, 2012 at 3:29 am #24823
    
    Carl Blare
    Total posts : 0
    Fancy word for “Pre-Excitement” regarding the forthcoming trial of the carrier current equipment I have been gathering.
    The two LPB units are all polished, the 2-20 transmitter and TCU-30 Coupler, for their maiden send-off coming soon.
    Everything is on hold pending the arrival of the crystal from ICM which will make it happen.
    Here is what I think will happen…..
    I will start at 2-Watts and find that the power line transmission is so effective I may never need 3-Watts. It will reach for miles and miles in all directions and my super-smart program schedule will show up on AM radios all over the area.
    People will listen and get smarter, they will come out their doors and fix the world and all of us will be saved.
    Send your thank you notes to carl@kdxradio.com
    - February 17, 2012 at 11:06 am #24828
      
      RFB
      Total posts : 0
      You mean after all that information and lesson and Q&A over PLL and oscillators…your still waiting on a crystal???
      That system should have been on the air within 6 hours of posting all that info on PLL and oscillators!
      Well no matter, the bigger thing is will those particular frequencies work out once those crystals arrive. At the going price (cheapest I found was 32 bucks) it will add up quickly and a bunch of useless crystals lying around.
      Well…if anything…it will be another lesson within the main lesson!
      Why do people always have to learn the hard way?!!
      :p
      RFB
    - February 17, 2012 at 4:30 pm #24831
      
      Carl Blare
      Total posts : 0
      To understand what I am doing and why I am doing it that certain way it is necessary to follow “The Time Line of Bitty Minutia.”
      1. One day I ordered a PLL circuit for application with Deep Voice long wave transmitter project;
      2. Then I learned that I’d need an oscillator circuit to make the PLL work but have been unable to find a long wave oscillator circuit;
      3. Acquired an LPB2-20 transmitter for carrier current but with no crystal;
      4. Found out I’d need an AM band oscillator circuit to use the PLL method but did not have an AM oscillator circuit;
      5. Ordered two crystals (570 & 670) from ICM;
      6. Was provided with schematic for an AM oscillator and buffer stage for use with the PLL, but too late to cancel the crystal order.
      7. However, in the future it may be decided to change the output filter of the LPB for mid-range use at 970kHz, which will employ the PLL method;
      8. Still looking for an oscillator for long wave use of PLL, but may give up and order crystal.
      Perfect sense from a part time thinker.
    - February 17, 2012 at 4:56 pm #24832
      
      RFB
      Total posts : 0
      Is why I said “patience pays”. See had you held on for a bit before ordering those crystals….
      But this may work out that the crystals will be at or very close to good frequencies to use..so there is still hope with that part!
      Part time thinkers get it right part of the time when partially parted from thinking on one part from another part and realize they left out a part. 😛
      RFB
    - February 17, 2012 at 5:18 pm #24833
      
      Carl Blare
      Total posts : 0
      The AM radio dial here in this location has a very distinct personality. There are only two stations listened to by large numbers of people, and both stations work to outdo each other with sports and loud brash-speaking so-called “personalities”.
      One of them is at 550 the other one at 1120.
      All the other stations are totally off the public radar and I’ve always wondered how they manage to stay on the air.
      The point for a part 15 station selecting a frequency is the question of whether to locate close to the only two popular stations, hoping to snag some of their audience, or to locate in the “safe” neighborhood of the obscure stations where a station could go un-noticed for years.
      Being close to the big sports stations might attract the wrong attention and invite shut-down action, even though we have no sports programming, unless you count the fact that I like to ridicule sports.
      Listeners themselves might get annoyed if they find us while thinking they should hear a baseball game.
      In a sense this is a game of self-applied diplomacy-politics and advance-damage-control.
    - February 17, 2012 at 9:45 pm #24834
      
      Carl Blare
      Total posts : 0
      The crystals have arrived from ICM one-week ahead of schedule, for carrier current testing on 570 and 670.
      But there will be a one-week delay anyway, because now it’s time to analyze the LPB2-20 Transmitter board by board, part by part, to verify its air readiness.
      Results of the analysis will be documented right here in the Carrier Current Journal.
    - February 23, 2012 at 4:49 am #24913
      
      RFB
      Total posts : 0
      Here is another project undergoing on air tests. It is a PLL board driving the exciter of an LPB AM-5 transmitter currently on air on 710Khz.
      LPB AM-5 Full View
      PLL Closeup (a bit fuzzy)
      It’s next test will be inside an LPB AM 25 transmitter.
      RFB
    - February 23, 2012 at 5:13 am #24914
      
      Carl Blare
      Total posts : 0
      I looked at those pics and saw what they looked like.
      They were quite interesting. They looked well planned and executed.
      I take from the experience a positive feeling, that I too could achieve a PLL driven transmitter.
      But not tonight. It’s almost midnight.
      Maybe tomorrow.
    - February 23, 2012 at 7:11 am #24919
      
      RFB
      Total posts : 0
      “I take from the experience a positive feeling, that I too could achieve a PLL driven transmitter.”
      The very reason why I posted those pictures is to show you that these transmitters can have PLL. This particular setup is operating in the lower 3rd of the band, which again demonstrates that your unit can operate with a PLL.
      When I put this PLL into the AM 25 unit, I will post those pictures as well.
      Remember, these solid state LPB AM transmitters all used the same A1 and A2 IC’s as well as the same balanced modulators and audio IC.
      Your unit’s exciter can also be driven by a PLL circuit, either the Datakit with the added oscillator, or one as shown in the images which has an on-board oscillator.
      Just wanted to help you toss aside any doubt about the PLL route for your unit.
      RFB
    - February 23, 2012 at 5:34 pm #24926
      
      Carl Blare
      Total posts : 0
      I am signed on to the idea of going PLL, but the idea was originally suggested in regard to the Deep Voice long wave transmitter project and I still need a VCO circuit in order to make that work. I have already invested in a PLL Data Kit, so I am half ready.
      For the LPB2-20 AM carrier current transmitter the PLL Kit and oscillator circuit are in hand, but the circuit arrived after I had ordered crystals for 570 and 670.
      The 570 crystal still makes sense, but I may have erred with the 670, because the auto radio clearly hears 670 “The Score” from Chicago, WSCR 50kW unlimited from Chicago.
      Another complication is that I would also like to try 970kHz, the clearest available channel, but the entire output filter of the transmitter would need to be re-built, so that may not happen.
      If there was a contest over cost, the crystal would be more economical, except in cases where there is a lot of frequency changing.
    - February 23, 2012 at 6:42 pm #24927
      
      RFB
      Total posts : 0
      The filter for the mid-band won’t be that difficult to construct because the manual has the part values needed for each of the 3 sections of the band. If you take a look at that parts list for the 3 filters, you can see that the toroid cores for the low and mid sections of the band are not all that different. Varying by only a few uH from one to another.
      Can’t wait to hear the results of the two frequencies your going to try!
      RFB
    - February 25, 2012 at 1:34 am #24944
      
      Carl Blare
      Total posts : 0
      For several days I have been removing, one by one, the circuit cards from the LPB2-20 carrier current transmitter, for serious inspection. This has paid off big time because I found a cold solder and a bent pin on an IC that was turned under the chip and not inserted in its slot.
      Also, the values of the 5 LP filter capacitors needed to be confirmed but couldn’t be seen without removing the card from the case. Luckily, they were all correct.
      This transmitter was built in 1981 and has gone through numerous lives under various owners, including a sex change from high band to low band.
      Now it gets re-assembled but we need a correct RF cable to link it to the TCU-30 Coupling Unit for test on the power works.
    - February 25, 2012 at 4:17 pm #24945
      
      RFB
      Total posts : 0
      “Now it gets re-assembled but we need a correct RF cable to link it to the TCU-30 Coupling Unit for test on the power works.”
      THESE are what I use to connect the
      TX to the coupler.
      RFB
    - February 25, 2012 at 4:54 pm #24946
      
      Carl Blare
      Total posts : 0
      Wow, thank you for that cable source. That is exactly the cable described in the LPB Manual. And it’s blue!
    - February 25, 2012 at 5:13 pm #24947
      
      kc8gpd
      Total posts : 0
      you can use any 50 ohm cable between tuner and tx.
      lmr400 is best. very low loss and high shielding
    - February 25, 2012 at 5:32 pm #24948
      
      Carl Blare
      Total posts : 0
      Yes kc8gpd, any 50-ohm cable, but the big trick is having a male UHF connector at both ends.
    - February 25, 2012 at 9:43 pm #24949
      
      RFB
      Total posts : 0
      The manuals recommend RG-8 if the coax run will be long. At the MW frequencies RG-8 will do just fine.
      Since it is most likely your TX will be sitting right next to the TCU, which is how my setup is, the linked source to the 3 foot long RG-8 coax will work perfectly, and is exactly the coax I am using at this very moment and there is no measurable loss at all.
      It’s real good coax and put together better than assembly line factory stuff. They are built by hand, by a ham radio operator and fully tested. You can get longer lengths from the vendor by request.
      RFB
    - February 25, 2012 at 10:03 pm #24950
      
      Carl Blare
      Total posts : 0
      The 3-foot length seemed perfect, because the equipment will be in a single location and any extra length would need to be coiled up.
      The LPB Manual says, “SO-239 UHF Type connectors, unbalanced, using 50-ohm coax cable. TYPE RG-8/U IS RECOMMENDED FOR SHORT RUNS (emphasis mine), Type RG-58/U is acceptable.”
      These blue hand-made cables fit the spec exactly.
    - February 26, 2012 at 3:24 am #24951
      
      RFB
      Total posts : 0
      “These blue hand-made cables fit the spec exactly.”
      That is why I posted the link to the exact cables I use. And yes they are exactly the type of cable specified in the manuals, again why I directed you to that vendor with the exact cable the LPB manuals calls for.
      Besides…why attempt something different when the exact type you need is readily available at a great price, and hand built and tested by a real radio person!
      RFB
    - February 26, 2012 at 5:16 am #24952
      
      MICRO1700
      Total posts : 0
      My friend just sent me an E-mail.
      It looks like I will have the
      LPB RC-6A in my hands on Monday
      or Tuesday, according to UPS.
      My friend is still writing up his
      report on the transmitter. This
      guy is extremely thorough when he
      has the time. He is very busy, so
      I’m not sure what to expect.
      But whatever he sends, it will be
      useful.
      As I mentioned before, my friend recommended
      running DC on the tube filaments – that will
      bring down most of the hum. I will eventually
      try that. He also recapped the transmitter.
      He said that was easy. I guess we’re looking
      at new tubes first. Another friend of mine
      surprised me and ordered a crystal for 1020 kHz
      from AF4K. A few problems came up. 1020 was
      not in stock. Since I can’t go below 1000 kHz
      because the crystals are so expensive there, he
      is now going to try to order a crystal for 1040,
      which is empty during the day, and pretty clear
      at night, too. There are two remaining questions.
      First, will the transmitter tune up on 1040? There
      is also a broken coil inside. The unit is working
      pretty well on 860, where it has been for years.
      (As you know, 860 is not a good channel here.)
      But again, it may not tune up on 1040 because of
      that broken coil. I told my local friend this, and
      it seems he is going to order a 1040 crystal anyway.
      We will see if a 1040 crystal is available, maybe it
      will be, maybe it won’t. The broken coil looks as if
      part of it has broken off on the bottom. Some of
      the “ferrite” is missing.
      A lot more may have to be done with the RC-6A. An
      oscillator may have to be built for a higher frequency-
      to be divided down into the AM BCB.
      All of this will take a great deal of time.
      Carl, if you are out there, you beat me out on the
      13.560 MHz rig, and it looks like you are going to
      beat me out here with this CC thing, too. I say all
      of this in jest of course. I am glad for you.
      Anyway, I will keep reading this journal, and
      I will let you know what happens here.
      I see this as an antique radio restoration, just
      like any other. So we will see where it goes.
      Best Wishes To All
      Bruce, Porch Light 2000(?)
    - February 27, 2012 at 5:34 am #24975
      
      RFB
      Total posts : 0
      That RC-6A can cover the entire band if the output tank is configured for it. The output tank is kin to the solid state unit’s low pass filter, which is split into 3 sections of the band..low, mid and hi.
      The RC-6A was built to specification of the customer’s needs, just like the solid state units were.
      If it was geared for the low band on the output tank, it will have a certain range it can cover on the lower third, same for mid range and hi range of the band.
      I posted some time ago about my RC-6A unit that was damaged due to a drunk brother ramming his Camaro into the wall which was part of my room and the table where the RC-6A was sitting got knocked over and SMASH..there goes the transmitter…it was built to cover the entire MW band and had an output tank coil with an adjustable inductor coil to shift the tank across the whole MW band. LPB made these particular RC-6A’s for sites that needed to change frequencies beyond one or more of the 3 sections of the band..ie from 700khz to 1400khz and so on.
      Wish I could remember where that manual is. Sheesh that was many a moons ago!
      But for your unit Bruce, a hunt for Red Inductor Core should begin now because either way, your going to need that second adjustable inductor to be working to cover the full range of the section of the band it is built for, otherwise it will be even more limited.
      RFB
    - February 27, 2012 at 12:13 pm #24976
      
      MICRO1700
      Total posts : 0
      The hunt for red inductor core.
      Very good!
      Actually, I was watching “The Hunt For
      Red October,” just a few weeks ago.
      I’ll have the RC-6A in my hands today
      or tomorrow. I can look at the coil
      and see what the deal is.
      My friend has yet to E-mail me his report
      on the transmitter. But I have a feeling
      because it’s taking a while, it will be
      a long report.
      I remember your brother’s (how do I put it,)
      contact with your RC-6A. I know he got you
      another transmitter. My memory says it was
      the 25 watt version.
      I feel badly for you – that you had to go
      through that. It must have been traumatic
      at the time. But again, you got a better
      transmitter. So, I guess we’ll leave it at
      that.
      Thanks for the info. I always enjoy it. I
      was telling some tech friend that you may
      be the most knowledgable CC person in the
      country right now. That we know of, anyway.
      There may be some other people, but they are
      in the woodwork somewhere. We are lucky to
      have you here. This is a subject that nobody
      knew anything about until you came along.
      Actually, KC8GPD knows a real lot of stuff. I
      had forgotten about him, but he’s way up there
      in the carrier current world, too.
      How much I don’t know, but his knowledge is very
      great, also.
      Well, let’s see what happens, and I’m really
      looking forward to Carl’s experience.
      Bruce, Radio Dumpster 909
      P.S. I’ve been coming up with all of these
      weird Part 15 station names to goof on Carl.
      I wonder what he thinks of this one?
    - February 27, 2012 at 6:41 pm #24984
      
      RFB
      Total posts : 0
      It all started back in 73 when a big box arrived that weighed considerably, containing two devices..the RC-6A and a TC-8 coupler. Previous CC operations used a home built 10 watt AM rig and a home made line coupler using LC circuits.
      Much of the self training came from reading a bunch of ARRL handbooks including the infamous issue I still have dated 1945, which had a plethora of information about CC. Many of the old ARRL handbooks of that era discussed CC as that was the only allowed radio operations during WWII.
      My grandfather willed them to me and I have a huge box full of them.
      To be honest, at first I was not really interested in broadcasting, or all that much interested in radio or CC transmission. I was more interested in high voltage Tesla experiments creating lightning bolts 20 feet long and scaring the entire neighborhood!
      Some of the experiments involved generating up to 500KV on coils standing 15 feet high. Fortunately there was PLENTY of room in the back yard to build such monstrosities.
      But as time went on, the interest in radio slowly started to come forth in me and it’s been at the forefront ever since.
      RFB
    - February 27, 2012 at 8:42 pm #24986
      
      Carl Blare
      Total posts : 0
      Actually the name Radio Dumpster 909 seems very normal to me.
      The word “dumpster” often gets mentioned, such as RFB locating an LPB transmitter thanks to a “dumpster tip,” and the terrible story of all of LPB’s inventory and manuals being pitched in a dumpster by new owners.
      I got several hundred pounds of 16″ electrical disk transcriptions pitched in a radio station dumpster, and there’s the fond story of my first streaming computer, and I feel a song coming on….
      When we ran an audio/video business, we used 100% Amiga computers because they had such strong television and graphics capabilities, but Amiga went out of business when the two owners suddenly grabbed the assets and moved to Bermuda.
      One day I saw an old PC out with a neighbors trash. I drove by it all day, and finally grabbed it and began to learn Windows, a platform we never wanted, but it seemed to be the only choice for the future. In the panel for “Computer Name” we entered “Dumpster.” It was the start of KDX Worldround Radio.
      And yes, we certainly are fortunate to have the members we have who know the field very well and make this the official part 15 website.
    - February 27, 2012 at 8:59 pm #24987
      
      MICRO1700
      Total posts : 0
      That’s really interesting stuff!
      Well, any kid would want to make
      lightning bolts that are 25 feet
      long. If I had the stuff to do
      it now – I would! And I’m 57 years
      old. It sounds like great fun. It
      would be great to have a hover craft,
      too. Some guys just built one. It
      was very very unique. It had a whole
      lot of little motors and props on
      some kind of frame work. There was
      a chair on top of the whole thing
      just sitting there. You could either
      fly the machine by remote control or
      you could get up in the chair and still
      fly it by remote control. (Except you
      are then sitting on top of the thing.)
      Somebody wrote the software for this
      hover craft so it sort of knew what it
      was doing, if you know what I mean.
      The machine is very stable. I wish I
      knew where I saw this thing on the
      internet.
      Still, lightning bolts that are 25 feet
      long might be better after all.
      I am very impressed that you built a
      ten watt AM transmitter and a coupler
      so long ago. I remember the 1963 book,
      Understanding Amateur Radio, from the
      ARRL had AM transmitter projects. I
      found it in the high school library when
      I was about 17 in 1971. It was the first
      time I saw a schematic for a real AM
      transmitter. But for various reasons, I
      was unable to built that sort of stuff.
      I’m wondering what you first studio was
      like. Did you build you own audio board,
      too? A lot of people did that then,
      as you know. There was no other way.
      It just sounds absolutely wonderful.
      Well, I’m off (but I’ve been that way
      a long time.) Thanks for the cool story.
      Bruce,
      Ameba Radio AM 530
      Paramecium Radio FM 88.1
      Euglena Radio 27.125 MHz
      Wonder what Carl will think of that one?
      Carl – when you get around to reading this –
      let me know if you are tired of hearing
      all of these made-up Part 15 station names.
      I’ll probably start running out of them
      soon anyway. Then again… maybe not!
    - February 27, 2012 at 10:09 pm #24988
      
      RFB
      Total posts : 0
      “I’m wondering what you first studio was like. Did you build you own audio board, too? A lot of people did that then, as you know. There was no other way. It just sounds absolutely wonderful.”
      As a matter of fact, yes. All built with salvaged parts from junked audio gear and televisions.
      BSE turntables, two 8 track recorder/player decks, two Pioneer reel to reel decks, and two Sony cassette decks and two AKG recording studio mics. Some of that hardware is sitting in storage back home all wrapped up in plastic, including the home brew audio console.
      All were wired up for stereo even though the transmitted signal was AM mono. The studio monitor system was also a Pioneer 150 watt home receiver amplifier pushing two Altec Lansing 1200 monitor arrays. I remember them well as they used to blast the entire house and surrounding area!
      The coupler was a mass mess of LC circuits comprising of 8 stages of tuned circuits. The first 4 were to match up the transmitter for 50 ohms and half of the first 4 were to tune up as a high pass filter to block any return AC hum from getting into the final and causing hum on the signal.
      The next 4 were to take the 50 ohm match down to the .2 ohm load on the hots, as well as half of it serving as a high pass filter blocking AC return from getting into the final.
      It worked really well, but due to the simple fact that it was a cluster of LC circuits subject to temperature effects and inductive effects, it was not capable of tracking the load changes on the line side from one part of the day to the next. It constantly had to be adjusted, mostly on the line side, and was a nightmare to keep tuned up. Thankfully the home brew TX was tube and tolerated such changes in the line inductance. The combiner and its 8 stages of tuned circuits did isolate the transmitter from those load changes somewhat, but no where near the 3000 to 1 ratio that the LPB TCU couplers had.
      When my RC-6A was replaced with a solid state unit, I used the same TCU-8 coupler and it worked great!
      Man that was so long ago. Brings back a bunch of great memories and fun times. Seems like that sort of thing could relive itself today if there wasn’t all this other nonsense going on in the world. I’m sure we all long for those days to return. In a way they are in our own way. As long as we remember those times and look back on those days, those times will never fade into the noise floor abyss.
      RFB
    - February 27, 2012 at 11:13 pm #24989
      
      Carl Blare
      Total posts : 0
      Dog 2, alias Micro, is welcome to keep the names coming and they will get phone calls on a future LPH. Is “Paramecium” a real word? Is “Euglena” a real name?
      I thought of a new name today also. Being withheld until showtime.
      The carrier current LPB2-20 Exciter is ready for a trial run this very night.
      EDITOR’S NEW THOUGHT: If MICRO 1700 had a son named “Mike” who merged with “The Crow”, he could be named “Mike Crow”.
    - February 27, 2012 at 11:37 pm #24990
      
      RFB
      Total posts : 0
      “The carrier current LPB2-20 Exciter is ready for a trial run this very night.”
      Oh my…calm down Carl! Let the exciter get excited! Your heart is racing so fast it’s causing tremors in the mantle! 😉
      But we all will keep a watchful eye out for the mushroom cloud and remember The Day After! 😀
      RFB
February 27, 2012 at 11:41 pm #24991

MICRO1700
Total posts : 0
1) RFB, I am blown away by what you did!
That’s the first thing. OOps now there are
two things – uh, three.
4) A Paramecium is a one celled creature that
has a whole bunch of little hairs around it.
5) A euglena is also a one celled creature.
It is neither a plant or animal, or both, depending
on how you look at it. Opps, that’s seven. It has
both food storage and chlorophyl. A really cool
little thing.
10) The LBP RC-6A arrived at my house at 5.48 PM.
11) But, I am at work! I will be looking at it around
midnight.
13 Bruce, Muddy-Hog Radio. Put your radio in a
garbage bag before listening. Opps, that’s 14.
No, it’s 15. Oh my God, it’s 16. OK OK OK stop.
18)
- February 27, 2012 at 11:48 pm #24992
  
  Carl Blare
  Total posts : 0
  Bruce Dog Studio:
  How is it that you know so many one-celled creatures?
  How do we fit in as far as cells are concerned?
  I have never owned a one-celled telephone.
  - February 28, 2012 at 12:32 am #24993
    
    MICRO1700
    Total posts : 0
    Seriously, I just was fascinated by the one celled
    creatures in the 7th grade, and some of the knowledge
    stuck in my brain.
    I always thought the euglena was cool. I guess there
    are something like 5000 varieties of them or more.
    There are beautiful pictures and films of some of these
    one celled animals on YouTube.
    So, wish me luck. Tonight when I get home, I’m going
    to check this LPB RC-6A out.
    As far as CC is concerned, you are really on track. It’s
    a good thing RFB is nearby.
    Best Wishes,
    Bruce, Dissolving Music Radio Zero (DMRZ)
    (Melts on your table, not in your car.)
    - February 28, 2012 at 1:02 am #24994
      
      Carl Blare
      Total posts : 0
      Take the rest of the week off because I just turned on the Exciter portion of the LPB2-20 into a 50-ohm load and it puts a fat signal at 570 just like a real transmitter!
      Here’s the part that departs from expectation: I was only testing the carrier, because I don’t have audio into it yet, but it had audio anyway, the exact audio from KDX 13.560mHz because the Big Talker transmitter is right there on the bench and the dipole is just overhead. Sounded good!
      I’ll be sending party girls to all the members, and wives need not worry because I’ll also send party men!
    - February 28, 2012 at 1:40 am #24995
      
      MICRO1700
      Total posts : 0
      YEAH!!!!!!!!!
      Pea-Pod Radio 2
    - February 28, 2012 at 2:12 am #24996
      
      RFB
      Total posts : 0
      “Here’s the part that departs from expectation: I was only testing the carrier, because I don’t have audio into it yet, but it had audio anyway, the exact audio from KDX 13.560mHz because the Big Talker transmitter is right there on the bench and the dipole is just overhead. Sounded good!”
      Title says it all.
      The last thing you need is some other transmitter with its antenna over the bench flooding the bench with RF while your trying to determine the LPB exciters carrier purity!!
      And the exciter is not in it’s cabinet where it would be shielded from outside influence like it is right now..hearing audio from another transmitter on a totally different frequency embedding itself onto that exciter!
      Your 13 meg TX is inducing strong RF onto that exciter board and if not careful, may damage it!
      No different from overloading the front end of a receiver…saturating it. That is what is happening right now.
      I suggest turning off ALL non essential transmitters while your benching that LPB!!!
      RFB
    - February 28, 2012 at 2:44 am #24997
      
      Carl Blare
      Total posts : 0
      Luckily that first test was a quick “carrier proof” and was turned off right away.
      Now the shortwave station is off for the night so I can run a tone generator into the LPB without interference from stray RFI.
      I will even get the exciter in its case where it will live a happy life.
    - February 28, 2012 at 3:37 am #24999
      
      MICRO1700
      Total posts : 0
      It sounds very very good. I don’t know
      why, yet. My friend has not yet sent in
      his report.
      I’m expecting new 6AL11 tubes tomorrow
      or the next day. My other friend across town
      has them. We just have to meet up.
      I put a dummy load on and plugged in an IPOD.
      I don’t know if the rig was running 100 percent
      modulation – but it’s up there.
      Audio response is good, it’s sounds very reasonable.
      It is on 860 kHz, where I don’t want to be, but
      we’ll worry about that later.
      It’s working a lot better than I expected. I wonder
      why?
      Bruce, DOGGRADIO STUDIO 2
    - February 28, 2012 at 3:49 am #25000
      
      Carl Blare
      Total posts : 0
      I notice you’ve run out of 1-celled station names, Bruce.
      How many cells are you running on?
      It seems maybe lucky that your transmitter is showing healthy signs of life.
      There’s another song coming on….
      It’s a lovely night for trans-mit-ters
      Spring air is filled with output pairs
      You carry my current
      I’ll carry yours
      Verticals that resonate
      Radials will radiate
      As we sing
      The part 15 serenade
    - February 28, 2012 at 4:15 am #25001
      
      Carl Blare
      Total posts : 0
      Just getting the audio generator hooked to the LPB2-20 for Exciter modulation tests into a dummy load.
      But also, thinking ahead, I think I’ll finally use the Volumax 4300 which has never before had a purpose except to fill up a rack space.
      Any opinions about the Volumax?
    - February 28, 2012 at 4:44 am #25002
      
      Carl Blare
      Total posts : 0
      The loyal and faithful Lafayette TE-20 Tube Tone Generator did its thing, especially since I upgraded it by adding a 600-ohm output transformer to give it a balanced output.
      This into the LPB2-20 Exciter Audio In, 600-ohm balanced, the VU meter swung into action and on a portable radio held close to the dummy load there it was at 570 on the dial…… 440Hz.
    - February 28, 2012 at 5:05 am #25003
      
      MICRO1700
      Total posts : 0
      It looks like we’re both getting
      somewhere!
      I just opened the LPB RC-6A up.
      My friend put a lot of new electrolytics
      in. He says it’s easy. Yeah! Easy
      for him! The broken coil doesn’t really
      look broken, but maybe I’m missing
      something.
      Concerning the two caps that you tune
      for max output. I thought they were
      coils, but they are caps. It looks
      like these things are tuned to the
      end of their range. They look to be at
      minimum capacitance. If I am correct,
      this unit may be at the upper end of
      it’s tuning range (at 860 kHz.) This
      particular RC-6A
      may only be for the low end of the band.
      RFB, I’ll have to look at your notes. I
      thought you said most RC-6As covered the
      whole AM band. So maybe I’m wrong there.
      I also see an inspection sticker on the
      inside. It looks like 10/5/71. But the
      “1” in “71” is a little squiggly. It could
      be a badly written “3.” So it might be 10/5/73.
      RFB, I think you knew exactly when this unit
      was made – start to finish. 1971 seems to
      make more sense.
      The only other thing I’m observing right now is,
      sometimes there is a whistle, maybe 6 to 8 kHz.
      If you tap the middle 6AL11, it stops. I remember
      this happened back in the old days. Maybe the 3
      new 6AL11s will stop that problem. Maybe.
      I have had this thing for about 30 years, and it
      has never been used on the air.
      I am glad to have it back.
      Bruce, Frog Horn 860
      P.S. Carl – just read you are getting 440 Hz
      through!!!! Congratulations!!!!!
    - February 28, 2012 at 5:28 am #25004
      
      RFB
      Total posts : 0
      No..I said that LPB did make RC-6A’s that could cover the entire MW band..but you had to specify that when the order was placed.
      My unit was just such a “all band” unit because I ordered it that way. It had the adjustable inductor coil.
      Obviously your unit is geared for the low band and has a different output tank.
      Carl, take note of the manual about the audio modulation percentage. 100 indication on the meter is way over. 100 percent modulation occurs at just under the 50 mark with program peak. Once set, the meter won’t display audio like that of a meter on an audio console.
      You can refer to the front cover insert of the cabinet for further info on the audio setup.
      However none of that is relevant until you get that exciter back into the cabinet, driving the final amplifier module. Remember this transmitter uses a linear final and is not a collector modulated transmitter. There will be re-adjustments once its all together and operating.
      Bruce..the 6 or 8 hz whine is probably one of the elements inside vibrating, sure sign of the tube being old and in need of retirement.
      Glad to hear both you and Bruce are making progress!
      RFB
    - February 28, 2012 at 6:31 am #25005
      
      Carl Blare
      Total posts : 0
      Not doing any more transmitter work tonight, only sitting back and bragging about today’s accomplishment. If I had a date sitting here she would already be snoozing as I go on about meters and dummy loads.
      I must have had a good instinct, because I set the tone on the meter at about 55% since higher than that sounded too high on my radio.
      Looking at the stars and realizing that I am a star, I wonder many things. I wonder what would happen if everyone in every house hooked up a carrier current radio station?
    - February 28, 2012 at 6:31 am #25006
      
      MICRO1700
      Total posts : 0
      Thanks RFB. I’m glad you are with us!
      Bruce
    - February 28, 2012 at 12:46 pm #25010
      
      MICRO1700
      Total posts : 0
      RFB, I was looking back at your post
      about your homemade board and everything
      else you had working there. That’s
      amazing you were able to assemble such
      an incredible station. All the people
      I knew THEN were either running Part 15 or
      pirate radio. I had heard of a few
      people running CC stations out of their
      houses, but it’s just Part 15 folklore.
      Except there was some kid who was on 640 kHz
      and covered a big area. He had a really
      cool station in a big closet. Pictures
      of this station were in one of the
      magazines of the time, but I don’t
      know which one. Maybe if was Elementary
      Electronics. I’m not sure. I do remember
      his station ran a program called “Rock
      Over London.” This was sometime in the
      1970s. I was particularly taken by his
      great installation in the closet. It
      was a small but very beautiful studio.
      This kids downfall was when he tried to
      get on FM. The story I remember was that
      a local engineer did a legal Part 15 set-up,
      supposedly, but something went wrong and
      the kid was busted. It was too bad. I
      think he was really trying to do a legal
      operation. He seemed to cover a wide area,
      so it must have been neutral injection.
      Of course, my friends and I never knew about
      that approach. Things might have been very
      different if we had.
      Reviving this old gear is sort of like
      a time machine to me.
      I love this old stuff. A lot.
      Because of my limitations, my progress on
      the RC-6A will be very slow. I will be
      happy just to have it’s signal covering the
      house and yard for now.
      Carl will be taking the lead on this
      until I can find a way to get the LPB
      unit onto a better channel. I’ll have the
      new tubes into the transmitter in a couple
      of days. We’ll see how that works.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - February 28, 2012 at 6:48 pm #25016
      
      RFB
      Total posts : 0
      I remember restoring an old McIntosh 50 watt tube stereo amplifier a couple decades ago. Had one heck of a time finding certain parts which were proprietary, some of which I had to come up with alternatives. Certain sealed coils in the receiver section and some hardware pieces, not to mention no schematic to reference. Thus took the time (about a week) to manually draw up the circuits then moving on with the rebuild.
      It was enjoyable and the best part..watching it fire up and pumping out 50 watts (actually about 62) of pure warm milky stereo audio. Receiver section worked great and I think it even had a bit more sensitivity and didn’t spit out the garbage like the other superhets did, (I cheated and added some custom filtering and shielding) and lit up the evening with the orange glow of filaments.
      Wish I was there with you Bruce to work through that RC-6A unit. There is nothing like seeing the old stuff come alive and rattle the cages of all the new things that usually end up in the dumpster shortly after the warranty runs out!
      Built to last, built like tanks and it takes a heck of a lot of work to kill one! That is unless you have a drunk brother who slams his car into the wall of your room! 😉
      RFB
    - February 28, 2012 at 6:56 pm #25017
      
      MICRO1700
      Total posts : 0
      I really enjoyed the message you
      just posted. I just came home
      from one of my jobs and my back
      is sort of messed up. (It will be
      OK.)
      So I will have some comments for you
      but I will have to post them a little
      later.
      Thank you for the cool stories.
      Bruce, DOGGRADIO STUDIO 2
    - February 28, 2012 at 7:02 pm #25018
      
      RFB
      Total posts : 0
      Hope the back issue isn’t serious. Rest and take all the time needed to get better, as well as take time to restore the RC-6A. Your health is far more important.
      At least from your description of the RC-6A in it’s current state, is functioning pretty well regardless of the whistling tube and messed up tuning inductor on the output tank. And thanks to your good friend who re-capped it and inspected it, makes the rest of the restoring project that much easier to deal with.
      Take a break, relax and attend to the back problem first. No one is going anywhere, and the RC-6A won’t either. 🙂
      To your good health!
      RFB
February 29, 2012 at 12:00 am #25019

MICRO1700
Total posts : 0
Thank you for your kind words. It means a great
deal!
Sitting in front of me is a box containing 3 new (NOS)
6AL11s.
Later on tonight, I will have time to try them in
the RC-6A.
I’m really excited about this!
Soon, I will have a couple of questions for you
about the transmitter.
In the meantime, thank you again for the kind words.
I will return soon.
Bruce, DOGGRADIO STUDIO 2
February 29, 2012 at 5:42 am #25027

MICRO1700
Total posts : 0
I just put the “new” (NOS)
6AL11s into the LPB RC-6A.
The tubes are from Sylvania,
which makes sense.
It sounds good. Very low
noise, no hum. This wonderful
piece of radio history is built
like a tank.
I believe it is achieving 100 percent
modulation. (I’ll have to pull out the
scope to really know, but I’m not ready
to do that yet.)
I saved the old tubes, because the
transmitter sounded good with them
last night. (Unlike last year – before my
friend in New Jersey worked on the
unit.)
I’m going to let it burn in – in the
next few days (only when I’m around,
though.)
And then, RFB – as soon as I can –
I will have a few questions for you.
These questions may not be easy to
answer – but you are THE MAN.
Best Wishes,
DOGGRADIO STUDIO 2
- February 29, 2012 at 10:13 am #25031
  
  RFB
  Total posts : 0
  Sounds good Bruce! Keep the old tubes around as emergency backups. If they still work, they are still useful for that purpose.
  And I will do my best to answer the tough questions. 🙂
  Just found this that may interest you: LPB RC-6B .
  Be good to have handy for those impossible to find parts!
  RFB
  - February 29, 2012 at 1:47 pm #25032
    
    MICRO1700
    Total posts : 0
    Thanks RFB. Well, I don’t have the
    funds for that second transmitter.
    However, I urge somebody here on the
    site to get it and try carrier current.
    You will be preserving something very
    special.
    It looks beautiful and the frequency is
    sure great – 530 kHz. Unless you have
    something on 540, 550, or 560 that is strong –
    530 kHz would be perfect.
    I’ll be right back.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - February 29, 2012 at 2:00 pm #25033
      
      MICRO1700
      Total posts : 0
      Still, a member here on the board who is
      good with tubes and high voltage should
      snap it up. I see it has no case, though.
      So, without a case, you HAVE TO BE GOOD
      WITH TUBES AND HIGH VOLTAGE OR YOU COULD
      GET KILLED. There. I think it was a
      good idea to say that.
      Perhaps my urging for somebody to get it
      is premature. However, having it just sit
      out there doing nothing sounds a little sad
      to me.
      Bruce, DOGGRADIO STUDIO 2
    - February 29, 2012 at 2:17 pm #25034
      
      MICRO1700
      Total posts : 0
      A good friend here just located a crystal
      for 1020 kHz for my RC-6A. It may or
      may not work out for various reasons,
      but the cost was is low I am going to
      try it.
      1020 is blank during the day. There
      are no locals on 1000, 1010, 1030,
      or 1040. So again, it is worth a try.
      At night, KDKA 1020 bombs in from Pittsburgh, PA.
      However, that’s at might. I don’t mind
      running a daytime operation. As we all know,
      KDKA is one of the first stations that came
      on the air in the 1920s. Some people have
      mentioned a few other stations that maybe
      came on just a little bit sooner, but I don’t
      remember what they are or if the info is correct.
      In initial tests, I don’t expect to be covering
      any big area, anyway. For a while, it will be
      just in my house. Maybe for quite a while.
      I plan to be very careful when I go to couple
      into the AC line. By the way, KDKA is one of
      those few AM stations on this side of the U.S.,
      whose callsign starts with the letter “K.”
      There is another one nearby. It is KYW in
      Philadelphia, PA. KYW is on 1060. I think
      I’ve got that right.
      So, Mr. RFB, stand by. I will have these
      questions for you fairly soon, I hope.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - February 29, 2012 at 2:45 pm #25035
      
      RFB
      Total posts : 0
      Heck..it would give reason to break out the hammer, nails and some wood..build that puppy a cabinet!
      Polish it up, give it a nice Earth tone appearance, like a lot of the older audio gear that weighed a ton with wood cabinets! 🙂
      RFB
    - February 29, 2012 at 9:08 pm #25043
      
      MICRO1700
      Total posts : 0
      You’re right, a homemade cabinet.
      But we don’t really know if the
      thing works. It still puts
      the feeling in me of, I’ve got
      to have it – but that would be
      completely unethical of me to
      try to buy it.
      I really really hope that someone
      who truly appreciates it gives it
      a good home. Heck, the 530 kHz
      crystal alone is probably worth
      the money. That’s about what it
      used to cost to have a below 1000 kHz
      crystal made to spec. As recently as
      a few years ago, I had known of a source
      for those crystals. Now I can’t find
      any company that does it. RFB, do you
      know? I’m talking about plans for the
      distant future.
      Speaking of really tough old gear that’s
      built like a tank. I just got a space
      to put my Hammarlund HQ-140XA. This is
      because the DOGGRADIO computer died.
      I know of another source for another junk
      computer in the not so distant future.
      However, using this HQ-140XA is like
      being in heaven. As near as I can tell,
      it was manufactured in 1953 or 1954.
      It is working great, and is cosmetically
      very good. It actually would make a good
      monitor for the LPB RC-6A. Actually, I
      take that back. My Sony SRF-A100 would
      be THE monitor.
      Hang on to your hat, RFB. Those questions
      will be coming.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - February 29, 2012 at 9:48 pm #25045
      
      Carl Blare
      Total posts : 0
      KDX Swims With the Current.
      The RF cable just arrived neatly packed in a USPS envelope, gray in color, not blue, but I don’t think the color of the cable will change the performance.
      Tonight may be the all systems test for this carrier current project.
      And Bruce, I am very much following the progress with your transmitter, returned home after a long out of town stay.
      As far as auto radios indoors, I’ve always thought about that, but didn’t realize the antenna question would be a main complication.
      What about this….. since automobiles work so well with AM radio reception, how about getting cars for use as a transmitting antenna. It would take two or three cars to reach ten feet high.
    - February 29, 2012 at 11:03 pm #25047
      
      RFB
      Total posts : 0
      “But we don’t really know if the thing works.”
      True, there is always the unknown factor…does it function or no.
      One can make a pretty good judgement by examining the images provided by the seller very closely and looking for the obvious things that would indicate a non-functioning unit. Things like burn marks on the PC board, frayed wire harness, discolored resistors, puffed capacitors, and things like pings and dents in the faceplate, highly incorrect meter 0 settings, scratched meter face, missing knobs or evidence of pliers used where proper tools should have been used, pre elementary level soldering jobs with blobs covering more than the circuit pad, burnt wires at the tube socket connections, rusty metal parts, should I go on?!
      But even if one were to find such a disaster unit, having the extra around just might come in handy with a part or two that can serve as a temporary replacement until a new replacement part is located. And with these older transmitters, finding actual replacement parts in either new or new old stock condition is 99.999999999 percent impossible.
      And if the unit looks in great shape, as that one does on the link I posted, and if the seller has a very good rating, chances are very good that the unit is in working condition to serve as a backup transmitter in of itself.
      That’s the thing about collecting and rebuilding the older electronic devices such as your RC-6A. Having something around that will serve as a backup or emergency part source so the hunt for replacement parts can go on while your station is still on the air.
      I would get it but funds had to be spent for my wife’s surgery she needed a couple weeks ago. No worries there, everything is fine and she’s on her feet and happy as a clam! Dang those up front costs! But I don’t care, the money went to a vital and good cause because there is no backup that can replace or take the place of my wife.
      RFB
    - March 1, 2012 at 4:15 am #25050
      
      MICRO1700
      Total posts : 0
      RFB, I’m glad your wife is OK, and
      that she is happy. That’s real important
      after a medical procedure. Give
      her our best wishes!
      And Carl – hat’s off to you for the
      joke about stacking automobiles to
      make an antenna (One of your best,)
      your latest “Blaire On Air,” and
      LPH #25. I have a lot of comments
      about that, but, right now I’ll just
      say I like your character “PHLOTYLLA”
      (Not sure how to spell her name.)
      I like her slow voice instead of the
      fast one. An explanation for that will
      follow.
      Best Wishes
      Best Wishes, Clogged Pipe 1240 and 1450 Radio
    - March 2, 2012 at 5:29 am #25069
      
      Carl Blare
      Total posts : 0
      Here in the midwaste we are on the brink of going carrier current.
      Make a note of this date and time: at 10:30 PM, today, March 1, 2012, the LPB2-20 which we’ve been carefully rebuilding was connected by a shiny new RF cable to the TCU-30 Coupler, which was temporarily lost under last week’s pile of mail, and has been undergoing stress-testing into a dummy load.
      No, I’m not putting anyone down, “dummy load” is a radio term which you probably know, and everything is smooth at 570 on the deal.
      Probably by this weekend we will make the big plug into the power grid for the beginning of this historic radio adventure.
      Your limo will arrive at the appropriate time, tuxedo is optional, pets on leash are welcome.
    - March 2, 2012 at 5:51 am #25070
      
      RFB
      Total posts : 0
      Let it be known that yours truly, via a stack of emails, provided the proper guidance and steered the new KDX CC ship on course to its final frontier…CC broadcasting!
      Thank you Thank you Thank you!! (takes a bow!)
      Good night! 🙂
      RFB
    - March 2, 2012 at 4:16 pm #25081
      
      Carl Blare
      Total posts : 0
      From nuts and bolts to wirewound resistors, from BIAS voltage to step-by-step instructions, the carrier current equipment rebuild and proof-of-performance check-out could not have happened without the help of RFB, who spent an entire evening, not to mention weeks before-hand, to guide the project into shore (unlike recent cruise ships).
      Amidst the many great resources found on this website, RFB is the absolute master of carrier current, and has the devotion of a religious medical doctor to cure broken equipment and personally walk it back to operation.
      Then after a successful evening of launching a transmitter, he makes dinner for his wife.
    - March 2, 2012 at 6:48 pm #25084
      
      RFB
      Total posts : 0
      Thank you Carl! And let me also say that you are an excellent student and now you are an LPB transmitter engineer! If I had degree certificates I would issue one in a nice frame to hang on the wall for you to enjoy with pride!
      Yep, that’s right folks, Carl went through the course and passed with flying colors! Soon after becoming more familiar with how his new CC system operates, he too will be a valuable resource for information on CC systems.
      Here’s to the new KDX CC station! And salutes to Carl for being such a great and observant student!
      You graduated…now go easy on that bottle of champagne! 😀
      RFB
    - March 2, 2012 at 7:17 pm #25085
      
      Carl Blare
      Total posts : 0
      Well, I don’t drink champagne, I can’t even spell it, but my actual drink list would take up a lot of bandwidth.
      Here in the midwaste the weather is misbehaving, with a lot of wind and threats of storms, so it would be kind of a fatalistic thing if I threw the big switch to broadcast on the power lines and the power went out all over the mid-section of the country.
      Then I would drink champagne.
    - March 3, 2012 at 4:29 am #25104
      
      Ken Norris
      Total posts : 0
      “Dang those up front costs!”>/cite>
      Tell me about it!! As of right now, it looks like I’m going to have to sell off gear (microphones, digital recorder, compressors, reverbs, mixing console, studio monitors, etc. etc.) and close the studio because it isn’t paying its way and I can no longer afford the rent because of a couple thousand $$ co-pay left from my last surgery … and it wasn’t even that heavy, compared to my musician friend on Orcas Island who recently survived a heart attack. He’ll be lucky to afford his property taxes this year.
      It’s going to be rough … means I won’t be able to record nor operate my Part 15 station in the studio I spent 6 years building.
      Healthcare in America sucks, but I have no idea how to fix it, or I would do as usual and offer some sort of solution whether it works or not.
      I think I’ll gather some more data and do a show about it.
    - March 3, 2012 at 6:56 am #25106
      
      RFB
      Total posts : 0
      “Healthcare in America sucks”
      I do not want to even think how bad it will be come 2014 when the required health insurance thing becomes law for the entire nation. If one does not have any health insurance, you end up with a 750 dollar fine payable to the IRS.
      Now how did the IRS ever become involved with health care or health insurance???
      Will be interesting to see how it all turns out.
      That really does bite about having to sell the studio gear you spent all that time building. I am scrambling trying to hang on to as much as I can..but already I have had to let go of one piece of gear recently…and I know how your feeling.
      I wish I had a solution. About the only thing I can think of is a mass protest and we all ban together and just say “NO”!
      RFB
March 2, 2012 at 10:46 pm #25093

MICRO1700
Total posts : 0
For the meantime, this message will
have to be short – I’ll explain later.
(It’s no big deal – just some logistical
problems.)
Carl, I’m very happy for you, and RFB,
I’m happy for you because you were able
to help Carl.
If I can get my LPB CC rig onto a good
channel, there is a very good chance
I can get a professional CC coupler
to use (borrow) for a very long time.
It all depends if I can get the RC-6A
onto a safe channel. If I can’t yet,
I won’t be asking for the coupler
until I can.
We’ll see.
Best Wishes,
Bruce DOGGRADIO STUDIO 2
- March 3, 2012 at 12:40 am #25094
  
  Carl Blare
  Total posts : 0
  Before connecting everything for that final plunge, I went out in the wind and cleared some vines from the side of the building. The thermometer dropped and back indoors, we have been surveying our two frequencies.
  We have crystals for 570 and 670, since this is a low-band transmitter, and at 5PM while the sun was still up 570 was clear but 670 was the sports station in Chicago. But the critical hours were hopping and things changed fast.
  At 6:15 PM the sun was mostly down and 570 was alive with WNAX, 5kW from Yankton, South Dakota, but by 6:30 PM it was fading.
  At 6:15 PM 670 had cleared and was just a jumble of far off energy, but at 6:30 PM a Mexican Spanish speaking station was almost clear, somewhat drifting in and out.
  We may have to set up a schedule for using these frequencies when carrier current operation begins.
  - March 3, 2012 at 12:51 am #25096
    
    RFB
    Total posts : 0
    Yep that weather front moving along through the Eastern part of the nation is wreaking havoc and causing a lot of destruction and unfortunate deaths. And it is an unusual kind of weather pattern taking place. Storms like that are usually in the spring and summer time, not in winter.
    The unusual weather patterns are directly linked to solar activity. The most recent is Sunspot 24, which was pointed directly at Earth on February 29 and March 01, which coincides with the current weather activity along the East and in other parts of the nation and world.
    Our solar system is interlinked, and when the sun acts up, everything within the solar system is affected..even the most outer planet Pluto, which was registered by NASA almost 2 years ago as rising in temperature.
    SUV’s and carbon footprints do not cause Pluto to warm up..the sun does. And the sun will most assuredly cause climate changes here on Earth. It is no psudo science like the Gore Bore carbon tax nonsense want’s everyone to believe. IT”S THE SUN!!
    And to give more direct evidence of solar activity affecting Earth…just examine all the highly increased auroras up to the North which have been making their way further South and seen in areas never seen before.
    RFB
    - March 3, 2012 at 1:02 am #25098
      
      Carl Blare
      Total posts : 0
      The effects and affects from The Sun, which for some unknown reason is not ordinarily capitalized, neither are earth or the moon (?), are very definite and it has been widely reported that Gore Bore built a 3-million dollar home right at sea level by the ocean with the proceeds from his polar bear drowning movie (the polar bears weren’t drowning, they swim). If he really believed the oceans were going to rise 2,000-feet he would have moved to Santa Fe, 8,000-feet above sea level.
      What we need, however, is something we can pin on the SUV, a vehicle that looks like an over-sized tennis shoe / roller-skate and daily runs down nuns and school children as cell-phone talkers sit so high they are viewing the shopping mall a mile ahead, usually with a dog on their lap.
      I know. The high gas prices are to be blamed on the SUV. Logic at 10.
    - March 3, 2012 at 1:07 am #25099
      
      RFB
      Total posts : 0
      One way to learn how the solar system interacts is to take a set of ball magnets and suspend them on strings, arranged like the solar system, with a large one at the center as the Sun. Then take another ball magnet by hand and slowly move it closer to your hanging magnet solar system and watch how that moving ball magnet in your hand affects the other ball magnets.
      The planets, and the Sun, all produce a magnetic field, weak or strong, and are affected by one another as well as affected by other bodies moving through the system, such as meteors and asteroids.
      This will also affect how the weather behaves, on Earth and the weather on the other planets that have an atmosphere.
      RFB
    - March 3, 2012 at 1:33 am #25102
      
      Carl Blare
      Total posts : 0
      Wind is an interesting force, and I do believe that main stream science: meteorology, earth sciences and the like, teaches that movements of wind are generated by solar influence.
      I am always fascinated by the fact that it can be very windy in one location but very calm in another.
      Does the wind move radio frequency energy that happens to be traveling in the air?
    - March 3, 2012 at 1:40 am #25103
      
      RFB
      Total posts : 0
      If the wind had metal elements in it, like metal vapors or particles, then yes it would affect EM fields like that of chaff affecting radar signals.
      Then if we had metal vapor or particles in our air, we would be able to eat fire and drink lava.
      What does affect EM fields in our atmosphere are magnetic flux changes that occur, and the impact of the solar wind upon the magnetosphere, which is basically a bunch of emitting EM fields of incredible intensity from the Sun. This is why during the day, certain bands are affected in one way, and then at night, in another.
      Anxiously awaiting the results of the first tie in to the big grid! 🙂
      RFB
March 4, 2012 at 6:07 am #25111

MICRO1700
Total posts : 0
Ken, you’re not alone.
Nobody knows this, but I’m fighting
foreclosure. We have a lot of sickness
in this family, in addition to my eye
situation. I’m not blind enough to
get financial assistance, but I can’t
drive, and reading is very difficult.
I do not know now how long we will be in this
house. We have been here 21 years, but
the future is uncertain.
I say this not to make you feel worse, but
hopefully to help you feel better. YOU ARE NOT ALONE.
WE ALL have to maintain a sense of humor. And we are
all friends on this board. AND we are here for each
other.
Fortunately or unfortunately, Carl Blare’s brand
of humor has saved me from going crazy. As long
as I have Carl’s shows to listen to, I am OK.
Don’t worry Carl, there is no pressure for you
to make more. There are enough of them for me
to listen to for a long long time.
And to the tech guys, who I find inspiring –
Neil and RFB, just to mention two – you guys
have kept me going, too. I’m sure I have
left to lot of you guys out, but Neil and RFB
come to mind right now. (My brain is not
all there, that’s for sure.)
A couple of days ago, a new manager in one
of my jobs found out the details of my eye
situation, and he said, “That’s good, you’re
fighting it Bruce – keep going.” That was
one of the nicest things I ever heard anybody
say, and I barely know this guy.
Yes, this country is going through a ridiculous
time.
But we are here, and in spite of the disappointments,
and the loss of people and things that we like, we
still need to have fun. And this is the place
to do it. I may have to box up all of my radio
stuff and sell/throw away/store it. So be it.
But not today or tomorrow. Tomorrow I’m going to
work on the Carrier Current transmitter. Because
it’s fun. And Ken, I have thought of you a lot.
You are a GREAT GUY! Keep going forward. We need
you to do that.
We are here together and we are a wonderful unique
talented group. Let’s enjoy what we are doing.
And now for some really stupid humor.
Bruce, Submarine Radio Part 15 8 kHz,
Broadcasting From Under Narragansett Bay,
Speaking Very Slowly. Stay Tuned For
Our Next Word, Which We Will Say Tomorrow.
- March 4, 2012 at 1:16 pm #25112
  
  kc8gpd
  Total posts : 0
  the federal government is doing the exact same thing that they locked up john gotti for.
  the system is corrupted completely from child support system (states actually have income from C.S. collected and late fees, interest figured into their yearly budget) to tax system (the IRS doesn’t even understand their own tax code), to healthcare(the whole HMO system was designed via backroom deals in the 70’s to drive up costs and make $$$ for insurance companies).
  then i need not even get started on the NDAA recently signed that allows the USA to lock US citizens up indefinitely in fema camps (which are starting to come alive and be staffed) without a right to legal counsel. seems someone did that back in the 30’s and 40’s and we went to war in an effort to stop it. then there is the likes of reed, pelosi, weiner, clinton, etc. perves, crooks. a few caught evading taxes. then there are multinational mega corporations who use their vast coffers to influence public policy to make them richer all while having to pay less taxes on more income than we do. and then we come to the FED Reserve!!!! the most criminally corrupt organization on the planet next to the international bank (based in brittan did we not kick the brits out of here in the 1700’s?)who are the real people pulling the feds strings.
  if you do a show do a complete show on what has screwed this country into oblivion.
  - March 4, 2012 at 3:42 pm #25114
    
    RFB
    Total posts : 0
    “if you do a show do a complete show on what has screwed this country into oblivion”
    What we do in Part 15 radio is continue and expand upon what was once great radio.
    Part 15 radio can expand and continue to wake up the walking sleeping masses by doing things as creating programs that talk about this stuff, and help return what was once a great nation.
    The more who do it, or carry programs talking about it, the better. None, and I mean NONE of the mainstream nightly mind manipulating news is going to even whisper a word about it…because they are controlled by the same elites that work the Howdy Doody puppets you THINK you elect, when in fact they are already selected, and have been so since LBJ stood by to hop right into position made available for him by those same elites who pulled the trigger.
    The magic bullet, lone gunman are the multi-generational serial killer filthy beyond comprehension rich elites, same ones killing everything right now..and to come.
    RFB
  - March 4, 2012 at 3:58 pm #25115
    
    Carl Blare
    Total posts : 0
    Gentlemen, I cannot do that really big show until the carrier current station is on the air, and we are very close.
    I have been moving like a snail on each stage of the installation, especially the part about latching to the high power lines, which is now ready to go and the solution might be interesting to technical minds:
    To begin with, the power terminal screws in the LPB TCU-30, are somewhat small, and they are located in a tight lower left hand corner of the box… so it did not seem like a good idea to force the big thick three-conductor cable with stranded copper wires into that small space.
    The A.C. cable was salvaged from an old dryer that was hauled away last week. It will plug into the same outlet the dryer used.
    So I looked at RFB’s photos showing his carrier current installation, posted on the Low Power Hour Page, and got some hard copper wires of the same gauge he used, and terminated these in the TCU-30, but left them disconnected a foot outside the box, while I explored ways to inter-connect the hard wires with the stranded wires on the rubber cord…
    First, we tried butt-splices, also known as crimp-splices, featuring little cylindrical barrels which crimp down on the wires that stick into either end. But butt-splice devices work for stranded wire, but solid wire slips right out at the slightest pressure. No good.
    Tried twist on wire connectors, but they also seemed a little bit unstable given the loppy weight and force of the large wires….Not acceptable.
    RFB suggested large screw terminal block mounted in a little safety box with eyelet connectors crimped and soldered to the wire. So I spent a day going through my lifetime collection of parts and bits, but when does a collector have the exact part needed on a certain day? Answer: NEVER! So I went to Lowes and stood in the big aisle seeing that they didn’t have the parts RFB had suggested. I said the word “Dammmmmm..” and made it last for about 30-seconds, but then I saw something that triggered the inventor side of my re-cycled personality, and this may become the official carrier current connection technology…
    Eaton Cutler-Hammer Non-Fusible Pullout Air Conditioner Disconnect. It is perfect and has met the approval of RFB. It will be safe, and will always remind me of the day that I came up with a good idea.
    Today is hookup day. And be assured, we will be sure the circuit breaker is OFF when we plug the thing in.
    - March 4, 2012 at 4:44 pm #25116
      
      RFB
      Total posts : 0
      “Today is hookup day. And be assured, we will be sure the circuit breaker is OFF when we plug the thing in.”
      As I stated in your blog post Towering Thoughts, don’t let synchronicity become part of the project.
      And as I have said before..if you are not sure, STOP, RETHINK, REEVALUATE, REASSURE.
      Your playing with things FAR MORE serious and FAR MORE DANGEROUS than a piece of wire hung from the roof or leading to the window or a mere flea. Your dancing with the HV/HC devil and if you don’t dance right, you will do a dance usually referred to as BBZZZZZZZZAAAAPPPPP!
      RFB
    - March 4, 2012 at 7:32 pm #25117
      
      Carl Blare
      Total posts : 0
      Synchronicity only exists for people who believe in it, and I don’t.
      But synchronicity is a fun topic to debate, along with astrology and whether there is more than one easter bunny.
      But I am using that guideline….
      Right now I am STOPPED, getting set to RETHINK, may re-evaluate after that or perhaps STOP first. Here comes the thinking part…..
    - March 4, 2012 at 10:13 pm #25118
      
      rock95seven
      Total posts : 0
      Carl the suspense is killing me lol. But i think i can wait a bit longer. Sincerely Rock 105.3 – Broadcasting from the new Tornado Alley in London,Ky
    - March 4, 2012 at 10:53 pm #25119
      
      Carl Blare
      Total posts : 0
      Hello to rock95seven new Tornado Alley in London, not England, Kentucky!
      The suspense isn’t killing me thanks to extra safety precautions with that electric wiring. I keep finding a way of improving the safety factor, all being supervised by Mr. Carrier Current, aka RFB.
      But I am down in the cellar now, cleaned up the equipment rack, swept the floor, and checked the wall plug to make sure it was ready to go.
      The first test of a 2-Watt signal at 670kHz should happen this evening.
      First the question will be: “Is it coming in on radios all over the house?”
      When that works, the next test will be a drive to see what happens along the line.
      This is Carl Blare, at the new bowling alley named Tornado Alley.
    - March 5, 2012 at 4:37 am #25124
      
      Carl Blare
      Total posts : 0
      All safety checks having been made and re-checked, we went on the power line with 2-Watts of power at 670kHz, silent carrier.
      The signal was receivable on radios all over the building, and I walked a portable radio 100′ outdoors down to the street. Solid carrier.
      We made a list of things that need improving, but all-in-all, it was a successful test.
    - March 5, 2012 at 4:49 am #25125
      
      MICRO1700
      Total posts : 0
      It’s like waiting for Alan Shepard to
      take off in the first U.S. manned flight
      on top of a Redstone rocket!
      Carl, you’ve go the Right Stuff!
      Bruce, DOGGRADIO STUDIO 2
    - March 5, 2012 at 5:27 am #25126
      
      Carl Blare
      Total posts : 0
      Yes, I’m stuffy all right.
March 5, 2012 at 7:58 pm #25138

MICRO1700
Total posts : 0
Even I can’t think of an
answer for that one.
Bruce, DRS2
- March 5, 2012 at 10:08 pm #25139
  
  Carl Blare
  Total posts : 0
  We just had another high level meeting of top carrier current officials, and we are temporarily putting the CC project docked with no immediate travel plan.
  My electric system is not behaving as expected and there are complexities, so we are staying up all night until someone gets an idea.
  Radio might be jealous of me. After all, I have many transmitters, and maybe radio expects monogamy. It might not approve of polygamy. Maybe I need a few divorces.
March 6, 2012 at 12:08 am #25140

MICRO1700
Total posts : 0
Well, as long as nothing happens to you,
that’s the main thing.
I’m glad you guys made the decision to
stop for now.
As RFB said, every CC installation is
different from every other. And every
CC set-up can have it’s own special set of
unexpected problems.
RF can do funny things. I had a touch lamp
in the living room. When I was on 80 meter
cw, the lamp would go on and off. It was
keyed by my RF carrier. Then one day it
just didn’t work anymore. And it wasn’t
from a dead light bulb, either.
At one point, my Part 15 100 mW, 3 meter
operation got into the telephone. And that’s
not much power, either.
Carl, in your next Low Power Hour, you might
want to report your findings on this so far.
Then again, you may not want to do that yet.
I see that this thread has been read over
2000 times. There must be a lot of interest
out there.
Best Wishes,
Bruce, DOGRADIO STUDIO 2
- March 6, 2012 at 1:29 am #25141
  
  Carl Blare
  Total posts : 0
  Thanks again, MICRO1700.
  Even as the CC project gets side-lined I am already building LPH#26, and do intend doing some kind of report on the CC Project. If you have any suggestions how it might best be done, I am still wondering how to say it without being too dull.
  The 2,000 hits to this thread probably have something to do with the new “keywords” method of surveilling social websites. Suspect key words include “man-animal (DOG RADIO) and electric current (carrier current), to name a few.
  Imagine “terrorists” with their 1/10th of a Watt. The author Gore Vidal tried to explain that “Terrorist is just a metaphor,” but since so much of the attack on civil cultured society is based on inane word interpretation: “missing fingers, 7-days worth of food, Ron Paul stickers, attitudes about “Constitution,” it is not so much a culture war, as some have said, but a prohibition of culture.
  To ward off suspicion just be stupid.
  - March 6, 2012 at 2:34 am #25142
    
    MICRO1700
    Total posts : 0
    Carl, you are so much smarter than I am.
    Maybe I’m just tired, but I didn’t understand
    any of your last few sentences. You know
    what they say, “If the wind is blowing from
    the west, it’s warmer in the city than it is
    in the winter.
    I’ll be back in a little while.
    Bruce, DRS2
    - March 6, 2012 at 3:05 am #25143
      
      Carl Blare
      Total posts : 0
      Dear MICRO1700 Dog Radio Studio 2:
      You cannot fool the Part 15 Board. You are super clever, ultra smart, and have it going high style! You, sir, are a university employee for heaven sake.
      My “last few sentences” are not secret. They simply refer to recent things in the news. If you have not been briefed on these recent news stories, you will be. Everything comes to him who wonders.
      I am not smarter than anyone. We all know different things. What we must do is pool our knowledge.
      Our enemies want to divide us so we distrust each other.
      But they only do that because it is their job, whereas what we do is a hobby.
March 6, 2012 at 4:29 am #25145

MICRO1700
Total posts : 0
Do they know how to solder a
PL-259 on the end of a coax
cable???????
NOOOOOOOOOOOOOO!!!!!
That’s Where We Have Them Beat!!!!!!!!
Come to think of it… every time
I try to solder a PL-259 on the
end of a coax cable… the next
day…. it always falls apart…
- March 6, 2012 at 4:54 am #25146
  
  Carl Blare
  Total posts : 0
  Well, obviously the PL-259 becomes DIVIDED from the coax.
  It only makes my point.
  They may not be able to do do a PL-259, all they need to do is divide yours.
  The plot is thick and we are thin.
  - March 7, 2012 at 5:03 am #25168
    
    MICRO1700
    Total posts : 0
    OK. My LPB RC-6A is working GREAT
    into a 50 Ohm dummy load on 860 kHz.
    As mentioned, this is not a good
    channel. Especially at night. During
    darkness, 860 is swamped by a Canadian.
    I would have to look it up, but I
    believe the station is in Toronto.
    On my Grundig S-350, the LCD “meter”
    is at max indication or close to it.
    If I run the transmitter into a dummy
    load, the signal goes about 5 feet regardless
    of what is on the channel.
    Then, I wrapped a bunch of extension cord
    around the coax cable feeding the dummy
    load. Then the signal went about 20
    feet. Keep in mind, there is a Canadian
    blasting in over the channel.
    Then I opened up the dummy load, and took
    the cover and resistor shield off. I
    wrapped the extension cord right around
    the resistor, and the signal went farther,
    probably about through the whole first floor
    of the house. It’s a small house, though,
    and there were peaks and nulls. If the
    Canadian station wasn’t blasting the channel,
    I probably could have heard the signal all
    over the house – even though it would be
    weak 30 or 40 feet away. By the way, the
    transmitter is very “on channel.” It’s only
    about 3 to 5 Hz off.
    Then I became concerned about one thing. The
    resistor in the dummy load is taking all of
    the RF power. With the extension cord wrapped
    right around it, that could be a problem.
    I started thinking that the resistor would
    probably be hot, and I did not want to melt
    the extension cord.
    So – I decided to touch the resistor with my
    finger to check it’s external temperature.
    It was hot.
    But – and this is the interesting part – when
    I touched the resistor with my finger – the
    860 kHz signal became much much stronger
    on the radio in the next room.
    It swamped the Canadian signal, and all I
    could hear was the music coming from my
    transmitter – the RC-6A.
    RFB – I have theories as to why this happened,
    but I want to know what you think first.
    I had to turn the set-up off, because I did
    not want to have the resistor compromise the
    insulation on the extension cord. Nobody
    wants a fire.
    So, what do you think?
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    P.S. By the way, all I am interested in
    doing right now is to listen to the RC-6A
    in the house. I am not ready to try CC
    right now.
    - March 7, 2012 at 6:21 am #25169
      
      MICRO1700
      Total posts : 0
      After my last “experiment” with “CC,”
      I put the RC-6A back on it’s dummy
      load. Then I plugged in some big band music,
      and put a radio next to the dummy load. (I had
      put the dummy load back together – the shield
      and the case are back on.)
      Even though the signal isn’t going anywhere,
      listening to the RC-6A’s signal is a joy
      to me. So I have been doing some late night
      chores, (thanks to my weird work schedule)
      and taking out some trash.
      When I got back over to the radio, I heard
      something different. There was a 300 or 400
      Hz tone on the signal, a het – from the Canadian
      860 signal and mine being on the same channel.
      Almost. My frequency has now drifted a few hundred
      Hz.
      Neil, if you are out there – you are right. We need
      crystal ovens. I am not up to building one right now,
      but maybe someday.
      Best Wishes,
      Bruce, DRS2
    - March 7, 2012 at 7:09 am #25170
      
      RFB
      Total posts : 0
      It increased because your body became the antenna. Ever try that on a radio receiver antenna port or a ferrite rod antenna by lightly touching them and the sensitivity increases.
      For the dummy load resistor, take some light grade sand paper and wrap it around the resistor, sand side towards the resistor, maybe two layers. Then wrap some #20 or #18 insulated hookup wire around the sand paper, single layer turns close wound. Wrap around the resistor/sand paper only, not the coax. Run the rest of the wire up and away, tack along the edge of the roof and wall, like running a leaky coax.
      Depending on the dummy load wattage, the more the better so that the dummy load will safely absorb the RF energy from the RC-6A and the more wattage the dummy load, the less heat it will give off. Warm is ok, somewhat hot is ok, but piercing hot isn’t so as long as it is not getting hot to fry eggs or roast a turkey, your fine. The sandpaper provides the insulation you need between the resistor and coil wire.
      RFB
    - March 7, 2012 at 7:15 am #25171
      
      RFB
      Total posts : 0
      Well the thing about crystal ovens is this. If the unit needed one, there would be one in it already.
      Crystals have an operating temperature curve with a stability range curve and if the crystal is not too aged, should remain within this range over the operating temperature range of the RC-6A. That is a tube unit, already producing heat. Your crystal is drifting off frequency the 300/400 cycles from operating for a time, which during that time heat is produced, as well as the crystal itself will get warm from operating.
      In Neil’s situation, his crystal was starting off cold and off frequency, thus the oven quickly brought the temp of the crystal up so that it’s on frequency. Depending on where your frequency is at start up, that may also require the use of an oven. But if it’s drifting this far after warm up time, then an oven is not going to solve anything. A fan to remove the heat will.
      RFB
    - March 8, 2012 at 4:32 am #25172
      
      MICRO1700
      Total posts : 0
      I’m getting ready to go to job number
      two, which is the day job.
      I wanted to thank you for your info.
      I will get back to you on this.
      Thanks again,
      Bruce, DOGGRADIO STUDIO 2
    - March 8, 2012 at 4:49 am #25179
      
      MICRO1700
      Total posts : 0
      Many Thanks to friend RFB, other
      tech-friends, and my
      other local and semi-local
      friends who supplied parts and did
      work on my LPB RC-6A carrier current
      transmitter.
      I have a signal covering my whole house,
      and a little bit of my yard. Although
      this transmitter is not being used for
      CC service right now – it is of great note that
      I have had it for 30 years – and this is
      the first time I have really had it on
      the air!
      Hopefully, carrier current operation will
      be a reality at some point. Right now,
      I am just enjoying listening to it through
      my radios in the house, and it sounds great!
      It am very happy to have this old tube rig on the
      air, even if it is not going too far. This
      is very satisfying for me. RFB, I still have
      some specific questions for you, but I’m really
      busy, and they will have to wait a bit.
      Thank you – thank you again!
      Bruce, DRS2
    - March 8, 2012 at 3:33 pm #25180
      
      Carl Blare
      Total posts : 0
      The news from DRS2 is great, his LPB transmitter serving the house, very good.
      The CC project here is pulled over to the side of the road during a few infra-structure changes.
      At the good advice of RFB the 30Amp circuit breaker feeding the coupler circuit has been taken out of service. The LPB TCU-30 Coupler does not draw any current from the AC, so the circuit breaker exists for safety of the lines, and 30Amps is too much.
      The helpful guy at Lowes called me and was sure he’d found a 5Amp circuit breaker (2-pole), available from another company. But when I called the other company they checked and did not have 5Amp 2-pole breakers. We’ll have to settle for 15Amps. but of course there are fast-blow fuses on each leg of the coupler itself, therefore safety will be very good.
      Also, both RFB and the LPB CC literature recommend getting the coupling equipment right at the electric panel, and our first test was done on a branch circuit about 100′ on the other side of the building, so we are moving things around to get the transmitter right at the panel.
      New testing should pick up this coming weekend.
    - March 8, 2012 at 7:21 pm #25181
      
      RFB
      Total posts : 0
      “Although this transmitter is not being used for CC service right now it is of great note that I have had it for 30 years – and this is the first time I have really had it on the air!”
      Actually, there is a little of both taking place. The RF field is emitting off the loose coupled wire, and at the same time it is sending it through the electrical wiring within the house. You could probably go three doors down and ask the neighbor if they pick it up on their small table radio using the AC outlet for power. This is only probable due to two factors:
      1. High power AM station on the channel.
      2. Not direct CC coupling onto the AC lines/neutral.
      To get a better direct CC coupling effect, just wrap that free end of the wire that remains after the coil around the dummy load, to a yard extension cord.
      This approach is obviously not as good as using a coupler unit but is a very basic method no different from coupler units. Just like the coupler units that provide the isolation and transfer mechanism, the method I described above does those two things as well. To improve the coupling efficiency of your basic CC setup, add more winding length around the yard extension cord, even more winding layers at shorter coil lengths, slide coil along length of extension cord to improve coupling effect.
      RFB
    - March 9, 2012 at 5:19 am #25184
      
      MICRO1700
      Total posts : 0
      Thank you Carl and RFB.
      RFB, I am going to have many more
      questions for your soon – well,
      as soon as I can. I just took a
      leave of absence from job number 2
      because of back problems. It’s
      no biggie.
      Carl, I know you will be reading this.
      We talked about that E-mail I was sending you.
      As you know, it was accidentally deleted.
      I will try to reconstruct it and send it to
      you as soon as I can.
      Talk to you soon!
      Bruce, DRS2
    - March 9, 2012 at 5:51 am #25186
      
      Ken Norris
      Total posts : 0
      “To improve the coupling efficiency of your basic CC setup, add more winding length around the yard extension cord, even more winding layers at shorter coil lengths, slide coil along length of extension cord to improve coupling effect.”
      Why would that not have such an effect on frequency that it would be very difficult to get centered?
    - March 9, 2012 at 9:11 am #25188
      
      RFB
      Total posts : 0
      Moving the coil across the length of the extension cord will allow for increased coupling or decreased coupling, like a variable attenuator. And depending on what frequency your operating at, the “variable attenuator” will have different results along the length of the extension cord because of wavelength.
      There is no difficulty with obtaining a maximum coupling point, it merely allows for adjustment just like an actual coupler unit.
      RFB
    - March 9, 2012 at 6:56 pm #25194
      
      MICRO1700
      Total posts : 0
      I can only stay on here briefly,
      because I have to get rid of this
      back problem, so I can go back
      to both jobs. I guess all of my
      messages will be short for a while.
      Now I got that out of the way.
      The coverage area of this improvised
      CC set-up is interesting. I get a
      strong signal all through my back yard,
      back about 100 feet. The RF field is
      coupling to my 100 foot long wire. After
      I leave that area, the signal drops off
      rapidly.
      The signal does get across the street, very
      very weakly. I tried walking down the
      street, and it doesn’t seem to be audible
      under the power lines. So the RF field
      is following wiring around my house, mainly,
      I think.
      I’ll have to experiment more when I feel better.
      Best Wishes,
      Bruce, DRS2
    - March 13, 2012 at 2:06 am #25227
      
      MICRO1700
      Total posts : 0
      I have discovered a nifty 10 dB attenuator
      on the net. This thing takes a 5 watt Rf
      signal and reduces it down to – you guessed
      it — 500 milliwatts. It is very clever. It is a
      PI net circuit. Each part of the circuit is a
      different resistance, of course. But the author
      of the circuit uses just 8 100 ohm 1 watt
      resistors in total. Different combinations of
      these resistors are used to achieve the desired
      values for each part of the attenuator.
      (Actually, the circuit is really a 9.6 dB attenuator,
      when everything is said and done.)
      I will have to make some changes to get this to
      work with the 6 watt signal from my LPB RC-6A
      CC transmitter, which is fine. It’s a good starting
      point.
      Assuming the above is done, the next thing to do
      is to feed the 6 watt RF signal from the transmitter
      into the attenuator. About 90 percent of the transmit
      power will be used up in the attenuator. This will
      accomplish 2 things. It will isolate the transmitter
      from the load, and it will provide a SAFE 600 milliwatt
      signal to feed into the coupler. (At least that is what
      I THINK!)
      The CC coupler will be something that I used from early
      experiments years ago. I have an AM BC band receiving
      loop. It will be used as a parallel LC and will be tuned to
      max. A length of AC line cord feeding the transmitter
      will be wrapped around the LC. How much I don’t
      know. I guess that will be part of the experiment.
      As RFB mentioned, this will have to be shielded. There are
      ways to do that. At first, for experiment’s sake, it will not
      be shielded, though.
      Hopefully, this will get some real RF into the AC line without
      causing significant problems to the transmitter or the house
      wiring.
      We talked about this before, but it is getting closer to reality.
      RFB, if you are out there, can you think of any other flaws
      or problems with this approach?
      It still do not have a crystal for the channel I want. But these
      experiments will be very brief, so no problems will come
      from them interference wise.
      It still have to build the attenuator. Hope to have that done
      soon.
      Bruce, DRS2
    - March 13, 2012 at 10:02 pm #25249
      
      Carl Blare
      Total posts : 0
      The trans-basement roller-rack parade was finally able to roll from the east wall of the sub-ment, or basement, or sub-basement, or sub-floor, over to the west wall, for it’s new home right next to the panel.
      Yesterday a ground rod was found out in the ivy where the panel upgrade of 2007 took place.
      All parts and pieces are here, the grid is running, part15.us is turned on, we are THAT close (hold fore-finger right near thumb).
      CC testing could even start tonight!
    - March 13, 2012 at 11:54 pm #25250
      
      Carl Blare
      Total posts : 0
      After not much happening for a long time, today has been highly fruitful as we have gotten 100% wired-into-place and totally verified by a safety expert.
      So as to pace it out just another mile, it’s time for dinner!
      We will be back later with a CC report directly from the scene!
      Cancel your evening plans and stay close to your computer.
    - March 14, 2012 at 3:04 am #25252
      
      Ken Norris
      Total posts : 0
      Waiting to see what happens. Will you do a drive test?
    - March 14, 2012 at 3:36 am #25253
      
      Carl Blare
      Total posts : 0
      Did not get to the drive test, but it will be very interesting. I’ll tell you the best and work backwards.
      The carrier at 670kHz is full-scale on every radio anywhere in the entire yard, no hum problem, running 2-Watts.
      Once the SWR was tuned with no audio, I put a 440Hz tone on the air, and with just a nudge at the bottom of VU is is very loud on the air.
      Now the downside. The best SWR (Standing Wave Ratio) I can get is 3:1.
      The top of the GREEN area on the meter is at 2:1.
      I think I remember those numbers correctly, but I’m on the wrong floor now and not going back down tonight.
      Let it run for 2-hours and all was stable.
      Tommorrow… DRIVE TEST!
    - March 14, 2012 at 4:46 am #25254
      
      MICRO1700
      Total posts : 0
      So that means there is some
      reactance somewhere.
      It’s too bad you can’t tune it out.
      However, I am very glad to hear
      about your modulation and range
      test. That is very encouraging!
      Best Wishes
      Bruce, DOGGRADIO STUDIO 2
    - March 14, 2012 at 5:39 am #25255
      
      Carl Blare
      Total posts : 0
      It’s probably that one woman down the block. She’s always reacting to me. And it’s never good. I think she has it in for radio.
    - March 14, 2012 at 6:36 am #25256
      
      RFB
      Total posts : 0
      “So that means there is some
      reactance somewhere. It’s too bad you can’t tune it out.”
      Yep. However it does not necessarily mean the reactance can’t be tuned out.
      By adding additional capacitors on the output terminals between line and neutral, that might help bring the couplers on board capacitor bank into range and tune the reactance out.
      At this point things are better than they were with the first attempt. A 3:1 ratio is not good, but not all that bad either at the power level range Carl intends to operate at. The coupler will always keep the transmitter seeing a proper load and that 3:1 vswr will not affect the transmitter or what the transmitter sees on the input side of the coupler.
      Progress in the right direction! And remember, CC is a flux science and every setup will have it’s own unique issues to work out.
      The adventure has just begun!
      RFB
    - March 14, 2012 at 4:29 pm #25259
      
      Carl Blare
      Total posts : 0
      This morning 10 AM CDT set out east with tone on 670kHz CC.
      Three blocks later the signal was gone, not quite as good as 1680 AM with the AMT5000. But of course in the case of CARRIER CURRENT we are measuring carriage along the power line, a different technology.
      It would appear that our power transformer is not bypassed in the way that would allow the signal to travel farther. It doesn’t appear to be bypassed, but we gave it the chance to prove us right or wrong.
      All this with 2-Watts.
      SWR (Standing Wave Ratio) was worse this morning: 4:1. Last night it was 3:1. The top of the GREEN SCALE says 2:1.
      Next stop.. Neutral Injection. Seat belts suggested.
    - March 14, 2012 at 4:57 pm #25261
      
      RFB
      Total posts : 0
      Not bad for being on the hots. Usually the blocker (utility transformer on the pole for those not following along) puts a stop long before a 3 block run. There obviously is far more than just a few houses tied in on that transformer, and probably will explain why the inductance is so high and
      difficult to tune out the excess reactance.
      As I pointed out way early in this venture..neutral loading will be the way to go.
      On to the next mission.
      RFB
March 15, 2012 at 12:53 am #25269

MICRO1700
Total posts : 0
A very good friend of mine received a “new”
fundamental crystal for my LPB RC-6A in
the mail. He will be getting it over to
me in the next few days.
The crystal is for 1020 kHz, which is empty
here during the day. The 1020 spot does not have
any local stations around it for several
channels. The rock is an FT-243 (NOS) ordered
from the AF4K website. AF4K sells cool
old radio parts.
The crystal was not very expensive as far
as crystals go. But I am grateful to my
friend because we do not know if it will
work in the RC-6A transmitter. But he said
he would get it for me anyway. He’s a real
good guy!
As mentioned before, some manufacturers
might still make crystals that are below 1000 kHz.
And, crystals lower than 1 MHz might have a better chance of operating correctly in the transmitter, which
is now working fine on 860 kHz. Also, we
do not know the transmitter’s actual frequency
range, so 1020 may be too high a channel.
The last time I checked for crystals that
could be made to spec for lower than 1 MHz,
I only found one company that would do it.
It was also very expensive – about $75.
And that was many years ago.
So, we will try the 1020 kHz crystal.
Once I have it in hand, I will
have to make an adapter for it to fit into
the RC-6A crystal socket, because it is in
an FT-243 holder. That will be easy, I have
an old empty crystal holder that will fit
in the RC-6A’s crystal socket. I can wire
the 1020 FT-243 holder pins into the
bigger empty holder – and then plug it in.
Then there will be the unknowns. Will the crystal
oscillate and be on channel? I won’t mind if
it is a little bit off. We’ll see.
OK RFB. It’s almost time for me to ask you
those specific questions about retuning the
LPB RC-6A. I am almost afraid to do it,
because it is working so well on 860 kHz.
We have several medical situations going on
here. When things slow down, I will start
to try this.
RFB, I might pose my questions soon anyway,
just so I can tuck any info you provide
away in the DOGGRADIO tech notes.
Very Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- March 15, 2012 at 1:16 am #25270
  
  Carl Blare
  Total posts : 0
  For some of us, and I am sure this is true for Dog Radio Studio 2, the Part 15 pursuit IS medicinal. It makes us feel better.
  If your ailing family members would open their hearts to Part 15 their recovery would be very rapid.
  But they are lucky simply to be close to a Part 15 man. The RF energy passes from one to the other.
  May your crystal bring you much frequency.
  - March 15, 2012 at 1:48 am #25272
    
    MICRO1700
    Total posts : 0
    I do appreciate that!
    By the way, I sent you an E-mail idea
    that may be really stupid, so put
    your “anti-stupid goggles” on.
    ANTI-STUPID GOGGLES! Available at
    Muncho Mart, Best Selling, MOGGS,
    Wood Wools, FREEB-X, and other fine stores.
    This week only 1/2 price with coupon.
    Except in Alaska and Nebraska. Tell
    them Road Hog Moran sent you and get a
    free Fruit Phone! Only Peach and Grape
    available, as long as supplies last.
    Bruce, DRS2
    - March 15, 2012 at 2:17 am #25273
      
      Carl Blare
      Total posts : 0
      Bruce, I didn’t need the “stupid goggles” for your e-mail.
      It made perfect sense and speaks to thoughts I have as well.
      To be polite to general readers, it was advice about “content” on the possibly wide-ranging neutral injection carrier current radio station now under development. I agree with the advice.
      As a wise philosopher once said, “It must be suitable for public consumption.”
      Oh, but that’s a difficult quest. I think someone also said, “You must know your audience.” Well how….????
    - March 15, 2012 at 11:38 am #25275
      
      RFB
      Total posts : 0
      “As a wise philosopher once said, “It must be suitable for public consumption.”
      There is a flaw in that philosopher’s statement. The public consists of a very wide range of preferences and tastes.
      What may be “consumable” by one, will not be by another.
      Not everyone likes green eggs and ham.
      What that philosopher should have said, and thought of before hand is this:
      “It must be conformed to a specific group of the public to which is applicable to said group that would deem it suitable for their consumption”.
      The one size fit’s all prospective NEVER works. And never will.
      RFB
    - March 15, 2012 at 9:55 pm #25285
      
      Carl Blare
      Total posts : 0
      Hi. KDX is “The One Size Broadcasting Station.” If you don’t like it, what’s wrong with you?
      Went into storage and brought out the 8-foot grounding rod. My masonry guy thinks he can sink it with his railroad sized slamming-tool (I forget the name of those major hammers)… “pile-driver?”
      Ordered a 970kHz crystal. That will be the most open channel if everything tunes up.
      Getting prepared to test “neutral injection.”
      Latest line being planned for a single’s bar:
      “Hi. Name’s Carl, and you’d be impressed by me if you knew anything about carrier current.”
    - March 15, 2012 at 11:43 pm #25291
      
      MICRO1700
      Total posts : 0
      I have, right next to me on the desk, a
      crystal for 1020 kHz. This will hopefully
      work in my LPB RC-6A. (1020 is the
      preferred channel, for a bunch of
      reasons, which I think I had mentioned
      in a previous post.)
      The crystal is in an FT-243 holder. It is
      from my very good generous friend.
      The rock IS old. It says 1020 KC on the
      side.
      It will take some time for me to do the following:
      1) Make an adapter so the crystal fits in the RC-6A’s
      larger crystal socket.
      2) Test the transmitter into a dummy load and hopefully
      tune it up on 1020 kHz with 6 watts out.
      3) Build a 10 dB RF attenuator. (For now.) When it is
      hooked up to the LPB unit, hopefully about 600 milliwatts
      will exit the attenuator output at 50 ohms. This will
      isolate the transmitter’s RF out from the load. Most
      of the RF energy will be used up in the attenuator.
      The 600 milliwatts on 1020 kHz will go into a large LC.
      This LC used to be a passive AM BC DX loop. It will be
      tuned for max.
      Then an extension cord will be wrapped around the LC.
      It will be plugged into the transmitter and the AC outlet.
      The LC will be tuned for max again.
      For now, the transmitter will be grounded to a water pipe.
      An FM tuner and audio amp feeding the transmitter
      will be floating above ground – at least until the transmitter
      is grounded. I don’t see any problem with this, because
      this arrangement will never have any direct connection with
      the AC line, as far as I can tell. If anybody thinks I’m wrong –
      please let me know. (The AC outlet will be checked to make
      sure it is wired correctly.) The FM tuner and audio amp
      will provide the DRS2 station programming from the local house
      90.9 MHz FM transmitter. This is a weak signal, so
      I will be using a SONY HD FM tuner, which is very very
      sensitive and selective.
      That will be it for this experiment. I don’t know if it
      will work, but it is worth a try. I can probably get a
      commercial coupler on extended loan without any
      problem. But I want to try this first.
      If you guys have any comments on this, please let
      me know.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - March 16, 2012 at 1:18 am #25293
      
      RFB
      Total posts : 0
      “That will be it for this experiment. I don’t know if it will work, but it is worth a try.”
      A very well planned first home brew CC coupling attempt!
      The attenuator, if I correctly interpret the descriptive design parameters, will provide the very low level signal at the output point but further in will slowly in stages work back up to the 6 watt level at the input, all while providing the 50 ohm match for the TX, meaning a low impedance to high impedance 9.6dB attenuator. I see no reason to not proceed!
      I suggest running the TX into the dummy load for the initial testing of the new frequency crystal for stability and to ensure the proper loading on the final since it will not be tuned that high in the band, help keep the unit from over stressing the final prior to going
      through the attenuator/LC coupler setup.
      Look forward to the next stage and report!
      RFB
    - March 16, 2012 at 6:18 pm #25308
      
      MICRO1700
      Total posts : 0
      I know you have been busy the
      last few days, so thanks for
      your comments. AND for backing
      up the website comment info.
      I’m glad you gave me the green
      light on this thing.
      There is a lot going on here, so
      it will take me a while to get it
      going.
      My main concern is: will the 1020 KC
      crystal work, will it be on channel,
      and will the transmitter tune in that
      range.
      In the not too distant future, I probably
      will have some specific questions for you
      about 3 components in the transmitter.
      They are – the two compression caps you
      tune for max, and the tunable inductor –
      which has a set screw on it. I think
      tuning the inductor so that it has less
      inductance will bring the transmitter up
      in the band. That means the tuning shaft
      will be turned counterclockwise. This is
      good, because it is almost all the way
      down into the transmitter deck, where the
      tubes and other parts sit. (I think – I’ll
      have to check – it IS fairly far down, anyway.)
      The part of the shaft where the screwdriver
      is supposed to go is broken, so I’ll have to
      use a pair of needle nose pliers. No problem
      there.
      After the inductor is tuned for less inductance,
      I guess the trick is to tune the two caps for
      max RF out. At least going from 860 to 1020
      isn’t too far.
      It will take me a little time to build the
      crystal adapter, and the attenuator.
      Wish me luck!
      Bruce, DOGGRADIO STUDIO 2
    - March 16, 2012 at 7:56 pm #25309
      
      MICRO1700
      Total posts : 0
      I just reread your last post and
      understood some things that I
      didn’t understand before. So
      if MY last post seems a little
      lacking in a few areas, well –
      I understand things a little bit
      better now.
      Thanks again,
      Bruce,DOGGRADIO STUDIO 2
    - March 16, 2012 at 8:55 pm #25310
      
      Carl Blare
      Total posts : 0
      You never knew I was gone. But this morning after signing into the site, a disaster movie script started to unfold.
      The worker who is tuck-pointing my wall pointed out some shaggy roofing tiles that must have been ripped by the high winds a week ago. So I called my roofer and their answering machine took my call, so I would wait for the call back.
      Then the internet and telephone went dead so no one could call me, I couldn’t call out, KDX was unable to reach the streaming world, and a rain storm was starting.
      I drove to my auto service place to use their phone to let the roofers know my phone was broken, then went to the cable office and learned there were multiple outages in the area.
      The tuck-pointer drove the 8-foot ground rod into the earth in preparation for carrier current testing with the neutral injection method. The rod went in without hitting rocks or other obstructions.
      Five hours after failing, the internet and telephone came back, and I was able to speak with the roofer and that problem will be taken care of.
      The cable company called and I thanked them for getting it fixed. She told me that a “fiber had been cut.”
      This will be a happy carrier current weekend filled with excitement with the possible exception of an approaching asteroid.
    - March 17, 2012 at 12:20 am #25315
      
      MICRO1700
      Total posts : 0
      Sounds like another plot for the
      “LAST MINUTE RADIO THEATURE!”
      Bruce, DOGGRADIO STUDIO 2
    - March 17, 2012 at 6:30 am #25316
      
      MICRO1700
      Total posts : 0
      appeared on one of Carl’s Low
      Power Hour shows. I might be
      spelling it wrong because it’s
      2:10 AM local time here. Anyway,
      I think the show is very very
      funny. The Last Minute Radio Theater
      Or LMRT, as I like to call it – is
      also very short, which makes it funnier,
      I think.
      I just thought I should explain this,
      just in case anybody wondered what the
      show is. (It’s a show within a show.)
      It is now also 2:30 AM local time. Because
      of an unusual work schedule here, there is
      really no distinct day and night in this
      family.
      Well, back to the CC stuff. I am going
      to be firing up my CC transmitter tomorrow
      for some burn-in tests. The other
      parts of the plan will come as soon as
      I can get them done.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - March 17, 2012 at 10:02 pm #25325
      
      Carl Blare
      Total posts : 0
      The ground rod having been in since yesterday, I mounted a small American flag on the rod so the tuck-pointer wouldn’t trip over it, and stood back so he could tuck.
      Then at 3 a long lasting storm came along with mighty blasts of lightning delaying everybody’s work. Computers shut down for safety.
      Now at 5 PM the streaming has been turned back on but the rain keeps dripping, not the right time for electricity work.
      See you tomorrow, when carrier current will flow.
    - March 18, 2012 at 5:28 am #25327
      
      MICRO1700
      Total posts : 0
      OK. I have some good news and
      some bad news about the frequency
      change for my LPB RC-6A.
      The 1020 KC crystal works. I don’t
      know how robust it is, because it
      is an FT-243, but the transmitter
      is on 1020 kHz, now, and not too
      far off frequency. Only a couple
      of hundred Hz. Maybe I can get it
      closer to 1020.00 by doing something
      with an external cap – maybe.
      The bigger problem is – I can only
      get 2 watts out of the transmitter
      instead of 6 watts, with a dead carrier
      and no modulation. No matter what I
      do, or what I try with the adjustments,
      that is the best it will do.
      If I run modulation, the watt meter jumps
      up to 4 or 5 watts, but I believe it’s not
      supposed to operate like that. The watt
      meter is not supposed to move with modulation,
      right? When this happens, the neon light
      lights up also, but again, this does not feel
      right. This tells me that things may not
      be too far off, but I do not want to hurt
      the 6AL11 final RF section.
      RFB, you are familiar with the coil and the
      2 caps that are in there. It is my belief
      that this RC-6A is really just for the lower
      half of the AM BCB. 1020 is too high, but it
      is the best I can do right at the moment.
      1020 is a very good daytime channel.
      Even for me, with my poor eyesight, the caps
      and coil do not seem impossible to reach.
      I have not been really able to get a good look
      at the LC network without a good light, but
      is there anything I can do – such as changing
      the inductance or capacitance, as needed, with
      some external parts? I MIGHT be able to do this.
      RFB, I really need your experience now.
      What do you think?
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - March 18, 2012 at 8:29 am #25328
      
      RFB
      Total posts : 0
      Unfortunately my manual to the RC-6A was lost some years ago during a move. The RC-6A unit I owned had an inductor coil with 4 taps on it and was a bit longer than the band specific inductors. The tap closest to the ground point of the inductor was for the high band and the tap furthest away from the ground point was for the lower band.
      It may be possible to re-tap the current inductor coil to bring the LC circuit closer to resonance. The two caps may have to be changed as well, but the main part is that inductor.
      I know that’s not much to go on but this is all from memory and a few old notes I found in my file archives.
      One thing I do remember vividly is when I changed frequency from 750Khz to 1150, the tap moved from the point furthest away from the ground point of the coil to the tap closest to the ground point. Which specific points along the coil where the taps were in relation to coil turns I can’t remember. Once the tap was moved, it only took about a turn or two of the slug to tune it up, and about a quarter turn on the two variable caps.
      RFB
- March 15, 2012 at 11:03 pm #25290
  
  RFB
  Total posts : 0
  “OK RFB. It’s almost time for me to ask you those specific questions about retuning the LPB RC-6A. I am almost afraid to do it, because it is working so well on 860 kHz.”
  Well I would just install the crystal and see if the oscillator runs correctly and stable first and then if it does, move on to the final tuning issue. The only potential roadblock I can see is that damaged tuning cap on the output tank. But maybe it will not have that much effect if it cannot be tuned. Only way to find out is to just try and see what kind of output you get and attempt to peak using the other cap and inductor.
  The coupling idea sounds good so I would proceed with that and enclose it into a grounded cabinet to prevent excessive radiation from the home made air toroid coils.
  Let the adventure begin! 🙂
  RFB
March 18, 2012 at 1:35 pm #25329

MICRO1700
Total posts : 0
Thanks RFB.
Well, I would definitely START with
the coil.
Maybe I can use an external component
along with the coil to reduce the apparent
inductance.
This is going to take me a long time.
I guess it’s not a good idea to run
the transmitter in this condition –
is that correct?
Best Wishes and Thanks For Being There,
Bruce, DOGGRADIO STUDIO 2
- March 18, 2012 at 3:08 pm #25330
  
  Carl Blare
  Total posts : 0
  Thinking about Bruce’s results at 1020 compared to earlier results at 860, it does seem that the transmitter is not optimized for the higher frequency. That seems like the most likely reason for the lower output wattage.
  But could the crystal itself have less output or some other mis-match that would cause the weakened performance?
  How can the safety of the tubes be estimated while operating in this out-of-ideal condition?
  - March 18, 2012 at 7:25 pm #25332
    
    MICRO1700
    Total posts : 0
    Carl, your point about the crystal is well
    taken.
    However, (and this is only an educated
    guess) after dealing with lots of funky
    old basic vacuum ham transmitters, this
    is what I think:
    If the crystal IS oscillating – it is
    probably enough to sufficiently drive
    the next stage. (That’s just my guess.)
    The immediate question is: if I run the
    transmitter in this state, will it hurt
    anything. I looked up some specs
    regarding plate dissipation of
    the final 6AL11, which is a
    double pentode. The two pentodes in the
    envelope are not the same. There is a
    beam pentode and a dual control pentode.
    I am going to assume that the beam pentode
    section is the final RF amplifier. (I really
    don’t know for sure, but the plate dissipation
    of that section is 10 watts.) The other pentode
    section (the dual control pentode) has a plate
    dissipation of only 1.7 watts.
    The transmitter is supposed to put out 6 watts
    under the correct conditions. If the final amp
    is running at 50 percent efficiency, then we
    are looking at 12 watts input. Maybe.
    Under this present off resonance scenario, two watts
    are coming out of the RF connector on the back
    of the RC-6A. If 12 watts of DC input is going
    into the tube, and 2 watts RF is coming out, then
    10 watts is staying inside the tube. That is
    the maximum amount a 6AL11 can dissipate. So
    I would call it borderline, depending on unknown
    variables that exist. And, there are plenty of
    real world unknown variables. So, it might be OK
    to run the RC-6A in it’s present condition.
    I REALLY WANT TO KNOW WHAT RFB THINKS ABOUT MY
    ABOVE OBSERVATIONS.
    I still have the old 6AL11s, I could just put
    one of those in the final socket, and if it
    gets soft, well, who cares?
    I know energy is staying inside the transmitter,
    because the transmitter is “Singing.” In other
    words, I can hear the input test audio coming
    from the inside of the transmitter itself. It
    is coming from SOMEWHERE, you know – without
    a speaker. I haven’t gotten my ear close enough
    to tell from where. But maybe the music sound is
    originating from RIGHT INSIDE the final 6AL11. From
    the beam pentode plate.
    I have to get back in there and stick my ear right
    into the transmitter deck. This will be interesting.
    Please let me know what you think.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - March 18, 2012 at 9:15 pm #25336
      
      RFB
      Total posts : 0
      “I REALLY WANT TO KNOW WHAT RFB THINKS ABOUT MY
      ABOVE OBSERVATIONS.”
      Absolutely correct. The power missing from the RF output connector due to the off resonance LC output tank is bouncing around in the final tube, as I noted earlier that this off resonance will present unusual loading effects within the final tube…and yes it will sing and sing and sing with every tone and note put through it in modulation.
      Not to mention some of that wattage will bleed over into the oscillator section of the tube. Basically the final is acting like a blender set on high and creating a mix mash of off-resonance mush within the final.
      RFB
    - March 19, 2012 at 1:12 am #25337
      
      MICRO1700
      Total posts : 0
      1) Carl! Congratulations to you!
      You are getting very close!
      2) RFB, you sure are right about the
      “singing” coming from in the transmitter.
      It is definitely coming from the
      modulation transformer. I’m pretty sure
      I can hear it from inside the final tube,
      also. It’s just hard to get my ear in
      there.
      3) RFB, if I break the connection at the
      hot end of the coil (not the cold end, and
      not the tap for the neon bulb) and put a
      small cap in there, such as 10 or 20 pF,
      will that bring the transmitter up in the
      band (if the tuning caps ARE NOT in the
      equation) THEORETICALLY??? Again, is this
      a place to start? It’s easy to do. Do
      you think this is a valid idea? Again,
      this is all theoretical. I am not asking
      for any specific component values. I think
      it’s just good to start with a small cap
      value.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - March 19, 2012 at 6:29 pm #25339
      
      Carl Blare
      Total posts : 0
      Ladies and gentlemen, by your feet you will notice some dirt. If you look closer you will notice a ground wire coming up out of the dirt and clamping to a copper ground rod just poking above the dirt. That was not as easy as it looks.
      RFB makes things sound easy. “Just sink a ground rod”, “just run a stranded copper wire out from the wall connected inside to the neutral connection on the TCU-30 coupler”. Easy as pie.
      Well I do not find pie easy. It took days of planning, strategy, tools, measurements, strength and time away from normal things like sitting somewhere and wondering what it would be like sitting somewhere else.
      But now it’s all there. The line output is firmly attached to the panel neutral buss and we are about to test the neutral injection method of carrier current part 15 broadcasting.
      The results will be ready just as the part15.us site switches over to the new super part 15 site.
    - March 19, 2012 at 7:53 pm #25341
      
      RFB
      Total posts : 0
      Making pies, especially from scratch is mostly a messy task where 90 percent of all the ingredients end up on the counter and floor and the remaining 10 percent is in the pie pan cooking in the oven.
      As I mentioned, it took me more than a month to discover that “easy” solution. The reason for that is because, and I restate it once again, that not every site is going to be exactly the same or require the same approaches to making it work. Every single location will be different, count on it.
      You discovered that hot coupling was..well not so hot after all. The vswr never got anywhere close to the upper green of the meter, and that in of itself is very odd.
      However this is a perfect example of how things vary from one site to another. Theory on paper is just that, theory.
      The real world is gonna tell you something completely different and will require some real world thinking and real world solutions.
      Your doing fine and making giant leaps for all mankind here! Since it’s been 42 years since the great gig trip, your progress is the most exciting thing happening today!
      Look forward to the drive test results.
      RFB
    - March 19, 2012 at 9:12 pm #25342
      
      Carl Blare
      Total posts : 0
      With the dashboard tuned to 670kHz and a low level 440Hz tone we headed west.
      The signal was there for the 1st block. The signal was there for the second block. In the 3rd block the signal was suddenly gone.
      That’s about the same result we got when the coupler was wired into the hots, but of course neutral is safer to work with.
      And now we have the Standing Wave (SWR) in a healthy green range.
      All this with only 2-Watts. Soon we’ll try 5-Watts.
    - March 21, 2012 at 4:15 pm #25361
      
      RFB
      Total posts : 0
      “The signal was there for the 1st block. The signal was there for the second block. In the 3rd block the signal was suddenly gone. That’s about the same result we got when the coupler was wired into the hots, but of course neutral is safer to work with.”
      Remember, your not transmitting off a central located antenna radiator, your transmitting off the power grid lines and that is going to have very different propagation results than from an antenna. For clarity..the TRADITIONAL antenna.
      There I said it so don’t need emails describing the difference or similarity!!
      Just because the car radio lost the signal at the 3 block point doesn’t mean the houses within that 3rd block can’t pick it up on their radios plugged into the AC outlet. The road test is only a part of the field reception testing. Your car radio won’t pick up the “far field” radiation at all because CC is NOT a far field transmission system. It is an INDUCTANCE FIELD transmission system.
      I suggest going to someone in that 3rd block area and knocking on their door, introduce yourself, what your doing and why, and ask them if they could check it for you on one of their plugged into the AC outlet radios for the signal. If your PR skills are still intact, this should not be a problem. Just look presentable, don’t carry around a briefcase as that is the sure sign of a door to door salesman and ye be met with a flying iron skillet to the head, and be neighborly.
      Long way to go yet. But your making progress.
      RFB
    - March 19, 2012 at 7:57 pm #25340
      
      RFB
      Total posts : 0
      “if I break the connection at the hot end of the coil (not the cold end, and not the tap for the neon bulb) and put a small cap in there, such as 10 or 20 pF, will that bring the transmitter up in the band?”
      Possibly. However the tap really should have a direct connection onto the inductor coil. You could try it and see what happens, but I think that will throw out the LC network from functioning all together.
      See our problem here is that we need to be going up and the inductor is wired for the low band. But that could work to our advantage. Everything is there already to shift this thing up the band using the existing coil inductor. The way to do this is to simply reduce the number of turns on the coil, or re-tap it further down the coil windings..ie closer to the cold end.
      Usually what I do with an unknown inductor in a situation like this is to imagine dividing the coil up into even segments. Then carefully place taps at each of those segments. This is a shot in the dark approach, especially for non-variable inductors. But in this case we have a variable inductor so we have some elbow room for the variables of the unknowns. It’s a place to start and with
      a little luck, just might hit the bull’s eye the first shot.
      What would help is finding the schematic to this puppy. I had no luck trying to find my old manual, that probably got lost way way back in the 70’s after getting the TX 2-20 replacement.
      The extreme approach would be to remove that inductor, and start unwinding it and then re-wind it and adding the tap points during the re-wind. I knew a guy who used to rebuild 1930’s radios and actually did just that, re-wound inductor coils, transformers, and even replaced no longer available tubes with solid state circuits inside the tubes with little light bulbs to simulate the tube glowing.
      Sometimes the extreme approach is necessary..but let’s see if that can be avoided here with your idea Bruce. It’s worth a try, and may or may not work, but we will never know until you do try it. Worst that will happen, it doesn’t work and you learned a new way of not doing the fix. It’s all a learning process…regardless if the approach is successful or not.
      Just remember that you got plate voltage present in that LC area so be careful probing around while it’s fired up.
      RFB
- March 18, 2012 at 7:36 pm #25333
  
  RFB
  Total posts : 0
  “But could the crystal itself have less output or some other mis-match that would cause the weakened performance? How can the safety of the tubes be estimated while operating in this out-of-ideal condition?”
  Well fortunately the RC-6A isn’t a suitcase nuke and won’t bring about the end times due to a new crystal and off-resonant final! Worst case that could happen…well what is happening at this moment, low output power.
  I’ve never heard of a crystal making the oscillator oscillate in a “weak” state, it either begins oscillation or it does not. A crystal however can be inadequate in handling the current flow within the LC oscillator tank circuit and be damaged. This is more true with the tube based oscillators, but in either case, the oscillator either does it’s thing or it does not.
  The RC-6A uses one half of the same tube as the oscillator and the second half as the final. With the output LC tank out of resonance, it could be presenting an unusual loading characteristic within the tube itself but not so much as to worry about the quickest way to the underground shelter! :p
  “I guess it’s not a good idea to run the transmitter in this condition – is that correct?”
  I would not run it for any long periods of time without that LC output tank tuned properly. The off resonant LC circuit will cause the final section to draw more current than it would on resonance (dip in plate current at resonance) and is not healthy for the tube..will cause accelerated degradation and effectiveness of the tube if ran this way too long.
  RFB
  - March 18, 2012 at 8:34 pm #25334
    
    Carl Blare
    Total posts : 0
    Putting a path through a wall for the stranded wire out to the ground rod.
    Wall = 8″ thick;
    Present hole as drilled in 1-hour = 6.5″;
    Distance remaining = 1.5″.
    No rush.
    - March 18, 2012 at 8:37 pm #25335
      
      RFB
      Total posts : 0
      Sounds like you are on your way to making some ground!
      RFB
March 20, 2012 at 12:23 am #25344

MICRO1700
Total posts : 0
Carl! Keep going man!
We’ll all be waiting for
the 5 watt carrier current
test!
RFB! Thank you for the
words! I’m going to go
real slow at this LC thing!
330 volts is nothing to
sneeze at!
Thanks again,
Bruce, DOGGRADIO STUDIO 2
- March 21, 2012 at 4:21 pm #25362
  
  RFB
  Total posts : 0
  “I’m going to go real slow at this LC thing! 330 volts is nothing to sneeze at!”
  Will grab you by the booboo if your not careful! It will put a new meaning to the term “bedhead”.
  One of the variable caps, not sure which, but one of them at least will have that 330V potential on it. What I suggest is tracing it out. Find the output point from the tube socket to that variable cap, that will be the one with the plate voltage potential on it unless there is a coupling capacitor between the output point of the tube socket and the input of the variable cap. Even if that is the case, there is still danger in that area when the unit is energized. Even a 6 watt RF signal will cause a little burn.
  RFB
  - March 21, 2012 at 9:38 pm #25370
    
    Carl Blare
    Total posts : 0
    Based on the game “musical chairs,” the CC Project is requiring a round of “musical tuners”, as I need to move one FM tuner and replace it with a second FM tuner.
    The Techniques rack-mountable has been the STL (Studio Transmitter Link) delivering audio to the AMT5000 at AM 1680, the STL channel being 101.9 FM. But the tuner overshoots its shelf by about 3-inches, requiring care in walking past, and is now needed in the rack housing the CC equipment, as the STL for the newly arriving AM 970 CC.
    The tuner, re-conditioned this very day, a Panasonic, will be the replacement STL for AM 1680.
    We need a traffic-directing wand for all this tuner juggling.
March 21, 2012 at 11:28 pm #25375

MICRO1700
Total posts : 0
I had a problem doing that a few times.
When the FM tuner was placed next to
the AM transmitter it was feeding – I had
unexpected trouble.
The RF field from the AM transmitter was too
strong in this case. The FM tuner lost all of
it’s sensitivity because it was sitting in that
near field. The frequency difference didn’t
matter. As you go fourth and increase your
wattage, you might have this problem. Or you
might have it now.
The only solution that worked for me was separating
the FM tuner and the AM transmitter – and then running
a long audio cable between them. I suppose RF beads
or chokes, or something like that might help.
Also, you might want to turn off 1550, 1680, and 13.560
when you try this. Because with all of these transmitters
running, you might have RF mixing occurring somewhere.
Just a thought.
And RFB, I really appreciate all of your comments. i am going
very slowly with this CC thing. I don’t want to mess up
this nice old transmitter by shorting something out. (And
zapping myself in the process.)
Oh – I have received RF burns from ham radio equipment
several times. Everybody read that carefully. RF Burns has
not come over to my house. (Although I wouldn’t mind.)
But seriously folks, RF burns feel really really weird, and they
hurt, too. And man – it doesn’t take much power, either.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- March 22, 2012 at 9:19 pm #25391
  
  Carl Blare
  Total posts : 0
  Our new 970kHz Carrier Current Service to several square blocks of world terrain will be Opening Soon.
  Today the 970 crystal arrived, the tuck-pointing on the west wall complete, and the LPB System tuned for 970, bringing the lowest SWR (Standing Wave Ratio) of any of our test frequencies, 1:2
  For now a tone is going out, but tonight the audio gets finalized and program tests are set to begin!
  Now the same people who already can hear us at 1680 AM will be able to change their mind and switch to 970 AM. Those with extra sensitive radios can try 1550 AM, and around .4% of the population might chose 13.560mHz SW.
  Only one of our radio stations doesn’t exist, I’m talking about 167kHz LW.
March 23, 2012 at 1:36 am #25393

MICRO1700
Total posts : 0
We’re all pretty excited about this, Carl!
Keep us posted!
Bruce, DOGGRADIO STUDIO 2
- March 23, 2012 at 2:19 am #25401
  
  MICRO1700
  Total posts : 0
  As I have mentioned, my attempts
  to put the LPB RC-6A on 1020 have
  to wait a little while. This is the ideal
  channel, but the rig will have to be
  modified a bit for it to tune up correctly
  there.
  My plans are to put the transmitter back
  on 860 and continue the experiments.
  The RF out from the transmitter will go
  to a 10 dB attenuator which will isolate
  the transmitter from my homemade coupler.
  There will never be a direct RF connection to the
  AC line. This is sort of a “poor man’s” circuit
  that I want to try just for fun.
  The problem is: the transmitter puts out six watts
  and my attenuator circuit can only handle five watts.
  The attenuator circuit isn’t built yet, but I have all
  of the parts. I’m gong to try it anyway. I don’t have
  enough parts right now to build an attenuator that
  can dissipate more energy.
  I guess the worst that will happen is I might burn up
  some resistors. Maybe I can test it for short periods
  of time or detune the transmitter slightly so it puts
  out five watts instead of six.
  That’s where we are right now.
  So GO! CARL! Let us know what happens with your
  set-up!
  Best Wishes,
  Bruce, DOGGRADIO STUDIO 2
  - March 23, 2012 at 2:44 am #25403
    
    Carl Blare
    Total posts : 0
    Bruce your progress is slow because you want to get every detail just right, and that’s exactly why my projects take so long to complete.
    All day yesterday was spent re-building that old FM tuner I talked about which is needed to complete the carrier current project.
    The slowest thing today was spending about 4-hours hunting down my rack screws which I haven’t needed since the mid 90s, and strangely enough, I spotted the box at the exact moment I was about to give up for today.
    Now the Techniques tuner needs to have a cable with rca on one end and screw-terminal connectors at the other. Maybe I’ll do that tomorrow.
    To heighten the excitement I am listening to the background noise at 970kHz, and there’s a ball game that pumps in and out with ionospheric wobbliness.
    - March 23, 2012 at 4:35 am #25410
      
      Carl Blare
      Total posts : 0
      Got the Techniques Tuner mounted in the rack, put the “T” shaped antenna up in the rafters, just below the Wholehouse 2.0 up stairs at 107.1 mHz, getting a marginal signal which probably can be improved by fiddling with the receive antenna.
      The first RCA to wire-terminals cable I used did not work, and I found the ground side had come unsoldered at the RCA plug, so I tried a second one which got us on the air, carrier current, 2Watts, 970kHz, with under-modulation.
      But it really sounds good. There’s no hum at all, very very low standing wave, and even though the VU in the LPB isn’t moving much, the on-air audio is only slightly lower than average stations, and sounds very good.
      There will be two ways I can up the audio level…
      1.) remove the 630-ohm terminating resistor in the LPB designed for professional balanced lines that need 600-ohm termination;
      2.) install the Volumax 4300 so that I can drive full level into 600-ohms, have fast limiting, and convert un-balanced to balanced.
      I guess I’ll do the latter, since the Volumax has no other purpose.
    - March 23, 2012 at 3:54 pm #25418
      
      Carl Blare
      Total posts : 0
      The carrier current system is now on the air and testing.
      Last night I streamed “Mischke” from WCCO and noticed that when I walked across the room (main floor) the FM receiver (basement) would “swoosh” as I interfered with the STL (Studio Transmitter Link) signal being sent to the LPB AM transmitter.
      The FM transmitting antenna is a vertical cage-monopole suspended on an indoor 3-leg tower made from bamboo poles and setting atop a stool.
      The FM receiving antenna is a T-dipole and was strung horizontally.
      Simple solution. I tipped the T on its side, making it vertical, and the STL is now rock solid.
      About the STL frequency… which had been set to 101.9mHz. Well, the cage-monopole transmitting antenna had actually been cut for 107.1, so to get the extra edge of efficiency I re-set the Wholehouse 2.0 for 107.1
      Re-tuning the tuners left out one tuner, which I over-looked, namely that feeding 13.560, the Big Talker shortwave station, which has been sending a silent carrier for over a day with me pre-occupied with looking for rack screws. Now it’s fixed.
      The grass needs cutting.
    - March 23, 2012 at 9:35 pm #25424
      
      Carl Blare
      Total posts : 0
      For the first full day KDX CC has been carrying the day’s programs on 970kHz at 2Watts.
      The audio system is still a simple connection from the Techniques Tuner with somewhat low modulation, but the carrier is so quiet that it is perfectly listenable.
      As a 4 PM storm was mounting I drove west and noted that the signal coverage, from the vantage point of the auto radio, is a very consistent 2.5 blocks. This has been true with every test to date, even on different frequencies and when we had more SWR (Standing Wave Ratio).
      The 3 frequencies tested include 570, 670 and 970 kHz, and it appears that the combination of this transmitter and this power line connection defies normal carrier current performance in that the HIGHER the frequency the better the result. It’s usually the other way around.
      Another thing that has come to light is that on radios connected directly to the A.C. the signal is stronger than on portable or auto radios, and on one radio in particular, a Zenith Transoceanic, the mid-band is somewhat clobbered by 970, and the audio is very present over a wide area, possibly swamping a few nearby signals. This requires further scrutiny, but the stations in question happen ALL (3 of them) to be religious stations. Although it is a condition that does not affect all radios, the key question is whether someone on the immediate power transformer wants to listen to these stations. If so, I need to back up. The rule is blunt: “…Cannot cause interference.”
      Because this CC installation is proving SO efficient on 970kHz at 2Watts, I may need to lower power, which of course is doable.
      And once more let us remember, the success of this project is due entirely to the guidance of RFB, without whom I would be trying to figure out where to store a very clunky bad purchase.
    - March 24, 2012 at 1:42 am #25429
      
      Ken Norris
      Total posts : 0
      Is it true that the lower the frequency, the more opportunity for interference? Electric motors, power transformers, florescent lights, etc., especially down low.
      I forgot what coupler you’re using. OTOH, I think it’s great that it’s working!!
    - March 24, 2012 at 2:15 am #25430
      
      Carl Blare
      Total posts : 0
      The coupler is an LPB TCU-30.
    - March 24, 2012 at 4:14 am #25432
      
      Carl Blare
      Total posts : 0
      The whole day today was carried on KDX CC at 970 AM. All went very well.
      At 11 PM when I shut the carrier, I heard a station coming in with fund raising for wpr.org. Never having heard that before, 970 is usually a mish-mush of indistinct stations, I traced it to Wisconsin Public Radio, coming from WHA in Madison, Wisconsin, with only 51 nighttime Watts!
      In the daytime WHA has 5kW, but is not heard here.
    - March 24, 2012 at 11:17 am #25434
      
      RFB
      Total posts : 0
      “Is it true that the lower the frequency, the more opportunity for interference? Electric motors, power transformers, florescent lights, etc., especially down low.”
      Yes. Even more so these days with far more florescent lights (energy savers) and switching power supplies replacing linear based power supplies.
      Also things like BPL can wreak havoc across the entire MW band, some days its really bad, others the bizz buzzing is hardly there.
      Another factor is this clutter noise one day may make the lower 3rd useless but at the same time across town the noise is non-existent. It is as if the noise likes to bounce around along the grid, parking itself for a time in one area, then moving on to another.
      These and other problems that vary from one site to another is why CC is not by any means a one method or approach applies to all. For example…the “myth” about the lower third of the MW band being the best for CC. It really depends on how the grid is configured for a given area because even in the same town or city, one section of it’s power grid is configured one way, while another is a little different or a whole lot different.
      These differences in the grid system is why every CC location will have it’s own unique problems requiring unique solutions.
      RFB
    - March 24, 2012 at 1:09 pm #25436
      
      MICRO1700
      Total posts : 0
      Carl, you mentioned WHA, in Madison, WI.
      Again, one of those last three letter callsigns.
      I suppose it’s possible they left their daytime
      power on by mistake – sometimes that happens.
      But if the signal sounded fairly weak, then maybe
      it really was the lower power – what was that –
      51 watts?
      I have heard quite a few stations that are listed
      as very low power at night. Some of them sound
      like they REALLY are running their specified low
      power. Then – I know of some that really have
      mistakenly run the day pattern and power at night –
      very very rarely.
      Then there are some that just leave their daytime
      power and pattern on all of the time.
      I hear a station a few states away every night on
      one of the regional channels. It is supposed to
      run 22,000 watts day/directional and about 50 watts
      at night. Their signal totally dominates the channel.
      They must be running their day authorization at night,
      hoping the wrong people won’t notice. (Or the right
      people, depending on your point of view.) i don’t
      think it’s right – but their it is.
      Speaking of WHA in Madison, WI – years ago one of
      my FM DX friends heard the WHA FM transmitter here
      in Connecticut via E-skip. Man, it was BOMBING in.
      I remember that night well. Every channel on the
      FM BCB had about 3 stations. Because of the FM
      capture effect, and the rapidly changing characteristics
      of E-skip, stations kept changing rapidly on each
      frequency. It was impossible to get an ID on anything.
      But WHA held it’s own for a while, until the E cloud(s)
      moved away and other stations came in instead. A local
      station (well – about 20 miles away) was completely
      obliterated by a station from YOUR STATE, Carl!
      I really love scanning the AM and FM bands. Sometimes
      you just don’t know what you will pick up.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - March 24, 2012 at 1:17 pm #25437
      
      Carl Blare
      Total posts : 0
      Of the very few things I remember clearly, I distinctly recall reading that 20-Watts and above are required on the AM band to achieve skywave type skip. I would guess that the clear voice from WHA last night was 51-Watts, but I am only guessing. The signal drifted into the background and slowly came back for a few minutes, until I stopped listening.
      Public broadcasting in Wisconsin is possibly one of the most mature state-wide public radio networks in America. I remember hearing educational programs from the State network in grade school in the 1940s.
      KDX also skips. I remember one day I skipped broadcasting because I was out of town.
    - March 25, 2012 at 12:21 am #25441
      
      Carl Blare
      Total posts : 0
      The sun is setting on the second day of carrier current broadcasting at 970kHz with 2Watts. The audio quality is exactly as good as the AMT3000 & 5000 from sstran, and it is a remarkable technology.
      It seems to me that for the home installation only low Wattage is required. I think the FCC’s allowance of powers all the way up to 50Watts takes into account large industrial and institutional size CC where huge power systems require more push.
      I am guessing that a variable power transmitter with about the top power of 6 or 7Watts would serve the typical home station, and Doggradio’s version is right at 6Watts although not built for variable power, but there have already been discussions about using attenuation.
      I receive such a strong signal in the house that I may actually reduce power, although I suppose it will be tempting to see what happens with higher Wattage, maybe just one time.
      My problem now is that I don’t know which one of these stations to listen to.
    - March 25, 2012 at 2:11 am #25442
      
      Carl Blare
      Total posts : 0
      Thus far the carrier current experience has been a triumph, but certain worries are creeping in.
      I think I mentioned that on one house radio, a Zenith Transoceanic, the mid AM band is somewhat disturbed by the strength of 970kHz on about three religious stations.
      Now I have tuned across a kitchen AM radio and found that most of the dial is upside down, smothered, mixed up, not there at all, or very crushed.
      The power needs to be lowered. If anyone on this leg of the power service is unable to hear their favorite program on the station of choice it would be a disgrace in the part 15 community.
      Dreams are no more than bubbles in a haystack finding needles.
    - March 25, 2012 at 3:20 am #25443
      
      RFB
      Total posts : 0
      The adventure is only beginning.
      With all the transmitters going that you have radiating inside your house, and now a CC system added to that, is it any wonder why your radios are all freaking out??
      Remember a couple weeks ago when I said there will be something you will discover with all that going at the same time in such close proximity to the house wiring and the transmitters and antennas themselves, and that I would let you discover what that would be?
      Keep on going…much much more to discover! 😉
      RFB
March 25, 2012 at 4:04 am #25444

MICRO1700
Total posts : 0
I started composing this message when
RFB wrote his, just above. It took
me longer – so I just saw his reply
to you, Carl.
What follows, is my take on this before
I saw RFB’s reply.
Carl – yes – the radios in your house
are completely overloaded. So overloaded
that some of them do not function
correctly.
Those radios are almost directly connected
to your transmitter. Isn’t that right?
When I put a small AM radio right next to
the DOGGRADIO 1690 transmitting antenna,
that radio stopped playing altogether!
It went silent! There was so much RF
field there, that RF energy was induced into
various parts of the operating stages in
the radio. Amplifiers that required certain
bias voltages would cease to function because
the bias voltages would be incorrect.
Especially in the early RF stages probably.
RFB could probably word this better.
On the other hand, a radio plugged into
the wall socket of a house nearby is in a different
situation, in my opinion.
The RF field induced into the power line will
go through many changed before it even gets
next door. A quarter wave length at 970 kHz
is a couple of hundred feet, right? Before
the energy gets out of your house, even before
it gets into the next property, there will be
peaks, nulls, impedance lumps, phasing situations,
(in phase, out of phase) induction with other
objects – all kinds of things that will effect
your transmitter RF energy. A few hundred feet
of AC line after your transmitter RF out may
result in a very very different situation.
The signal could be much weaker.
Again, RFB can either agree with this idea or
disagree. I really don’t know for sure, but
it seems to make sense.
I just don’t want you to feel as if you are
causing some kind of harm. It is my bet
that you are not.
Also, if you turn off 1550, 1680, and 13.560,
your radios might function better – maybe?
However, RFB IS the expert. Let’s see what
he has to say about it.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- March 25, 2012 at 5:10 am #25445
  
  Carl Blare
  Total posts : 0
  Thank you good people for the points of view, and I will try running ONLY the 970 CC without all the other radiational stations, and we will see the difference.
  Another thing I don’t like is that tonight at midnight, when the programming ended, I had to climb into the dark basement to turn off 970. There is no way I’d want to leave a silent carrier on all night. There will need to be a remote control system added.
  They say there is no rest for the wicked, but I am kept so busy there is never time to be wicked.
- March 25, 2012 at 6:01 am #25446
  
  RFB
  Total posts : 0
  A round of applause for Bruce and his analysis of two very important points. The localized RF induction field within the home and the difference through the line variables when the signal arrives next door or down the street.
  The thing to always remember is that AC power wiring, be it in a building or strung across the landscape makes for a very VERY lousy transmitting antenna vs the conventional method of sending out a signal over a distance from a central point radiator cut and tuned to resonate at the transmitting frequency.
  The vertical 1/4 wave tower/antenna radiating a signal has only a few things to fight against to throw the signal, whereas AC electrical wiring, designed to carry voltage and current supply and not RF, has a ton of things to offer a CC system to fight against to get the signal to the receiver, most of which starts right at the source point, or coupling point. Such a roadblock was immediately found when Carl connected the coupler to the two main hots and the return path was the neutral. A high VSWR resulted and could not be tuned out even though the coupled signal did manage to find it’s way along the grid 2.5 + blocks (vehicle radio reception). Even with the high VSWR, his CC signal easily could have been received by radios plugged into AC power past the point where the vehicle radio lost the signal.
  The very nature of the electrical wiring and power grid system is what creates all these neat little things Carl has and is still discovering. A far cry from a simple wire or 3 meter stick out back…isn’t it! :p
  There are indeed similarities between a conventional radiating system and a CC radiating system. Both methods do put RF into the environment. Both methods create a very strong localized induction field, and both create a far field.
  The conventional MW vertical allows for the far field radiation to easily propagate away from the center point whereas electrical wiring and the many inductive things around the wiring such as conduits and vent ducts etc, quickly absorbs the potential for significant far field radiation pattern to be produced.
  Yes…you can and probably are overloading your radio receivers if they are sitting right next to that coupler or breaker box..including that FM tuner serving as the CC system’s STL receiver link. Yes, your other radios throughout the house will get a very strong signal and those closer to the coupling point an even stronger signal.
  Each one of those radios will react differently based on their front end sensitivity characteristics as well as detector and IF circuit characteristics and the distance from the coupling point. Sounds to me like Carl’s radios are simply doing what would be expected from typical radios within a location of a CC system. Now throw in all those other transmitters sending near field RF onto the same wiring the CC system is, all getting together and having an RF party with intermixing song and dance dinner, some of which will be amplified due to the stronger CC signal present, all within such close proximity to one another, is it any mystery that the radio receivers are going crazy?!
  Remember the testing of the exciter on the bench while at the same time a 13.560 transmitter was also in operation with it’s transmitting antenna directly ABOVE that same work bench putting a very strong inductive RF field (near field) right onto that LPB exciter..and audio was heard on what was supposed to be a non modulated carrier.
  Expand on that experience with this new experience of the radios reacting like they are. It’s the same cause and effect, localized within the walls of the dwelling. The chance of this happening next door or down the street is highly unlikely due to the nature of the loading characteristic of the power grid the CC signal is riding on. By the time it loops to the next house, and the next and so on, the inductive field (near field) strength is far less, and radios within that weaker inductive field will not be overloaded and going nuts like those within the very strong inductive field.
  The next round of testing and investigating should be done with just the CC system running and the other transmitters shut off. This won’t prevent your nearby radio receivers from being saturated, but you will remove any potential intermixing going on between all those generated RF fields in close proximity like they are.
  RFB
  - March 25, 2012 at 2:06 pm #25447
    
    Carl Blare
    Total posts : 0
    This morning we started by running only the 970 CC transmitter with an audio tone.
    The kitchen radio, a Panasonic table model from the 1970s, was able to scan the entire AM band with no stations in any way blocked by spurious signals from the CC. However, the tone was present at all times in the background as if the radio’s amplifier was detecting the station, not the receiver section. In fact I was able to pull in many out-of-town stations without interference. This radio is on a direct AC circuit that goes straight to the power panel.
    I turned on 1550kHz, AMT3000, located at the far end of the building feeding a Wintenna (the window frame is part of the 3-meter antenna). It did not cause any disturbance in combination with 970 CC.
    Turned on 1680kHz, AMT5000, feeding the Wintenna about 7-feet from the Panasonic radio. Now the radio started being a little blitzy, to use a technical term.
    But the most dial bloat happened when SW 13.560mHz was turned on, the indoor dipole arriving at its southern tip only 3-feet above the Panasonic radio. The Panasonic started flapping its tongue and rolling its eyes.
    RFB and MICRO1700 have been perfectly correct in their estimate of what is happening here at the Internet Building.
    - March 25, 2012 at 5:18 pm #25448
      
      RFB
      Total posts : 0
      “The kitchen radio, a Panasonic table model from the 1970s, was able to scan the entire AM band with no stations in any way blocked by spurious signals from the CC. However, the tone was present at all times in the background as if the radio’s amplifier was detecting the station, not the receiver section.”
      Sounds like this particular radio is in need of a front end alignment. 1970 eh…ya I bet those IF coils in there and their little caps across their coils have broadened their view of the world in all these years (component aging and drifting from tolerance).
      The reason why you heard faint tone across the dial as well as at the 970 point on the dial is because that radio’s IF and detector inductors have drifted from their factory adjustment points, which will make the radio see more than just what frequency you tune into. Add to that the proximity of that radio to the coupling point.
      “I turned on 1550kHz, AMT3000, located at the far end of the building feeding a Wintenna (the window frame is part of the 3-meter antenna). It did not cause any disturbance in combination with 970 CC.
      Again here is an example of the proximity factor. Further away from the receiving radio and adding the unusual radiator (window frame) producing an unusual field pattern from the shape of the radiator. Nothing unusual in that. But to really put it to the test, put that radio a couple of feet away from the Wintenna and I guarantee it will see a tone across the entire dial plus the tuned signal.
      See the puzzle coming together yet?
      “Turned on 1680kHz, AMT5000, feeding the Wintenna about 7-feet from the Panasonic radio. Now the radio started being a little blitzy, to use a technical term.”
      I am going to assume that your not feeding a single Wintenna with two transmitters are you? I hope not.
      Here we have a perfect example of near field inductive effects. 7 feet separate the radiator from the receiver.
      “But the most dial bloat happened when SW 13.560mHz was turned on, the indoor dipole arriving at its southern tip only 3-feet above the Panasonic radio. The Panasonic started flapping its tongue and rolling its eyes.”
      Isn’t that interesting. That 13.560 seems to do the most damage out of the rest. Understandable as it is putting out a bit more signal than the two MW 100mW units and on a much higher frequency. I do hope that thing has a good low pass filter on it. If it doesn’t, I suggest you keep it turned off until it gets one, or better yet, shut off until you get it a proper antenna OUTSIDE…on all of them would be the better and proper way to solve your intermixing over saturating issues going on.
      Basically Carl..nothing unusual or damaging is going on at all. You are merely experiencing what takes place with that many RF emitting devices in close proximity to one another as well as their proximity to receivers and the unusual radiators being used. Yep..chasing your own tail here my friend.
      Looks like a whole revamp and rebuild of your station’s transmitter arrangements will be required, starting off by putting that 13.560 onto a proper antenna outside. Same with the two SSTran MW units. They too are getting inductive near field RF from that 13.560 TX just like everything else is.
      It’s a good thing these TX’s are low power. But to a radio receiver with front end amplifiers and tuned circuits, it is no mystery at all why the radio receiver is acting like it is with all these intermixing RF fields bouncing around and in between the walls of your house.
      In a nutshell…the problem is localized and within your own home. The fix is known and should be done. I hear the summers there are nice and perfect for doing some outdoor activity….like setting up proper antennas for these 3 transmitters!
      Besides all that..isn’t the point to get the signal out to listeners BEYOND the confines of the walls of your house??
      If all you want to do is broadcast in the house, then put attenuators on those TX’s, especially the 13.560 and shorten their antennas so the near field being produced is less destructive. Your lucky so far that all of this, even prior to the CC system, has not over driven all the radios you have and or done some damage to other circuits in other devices.
      Remember our two friends…(a) and (b). Now include a (C).
      The (C) is the first letter of your first name, and it is the (C)’s arrangement of these things that is the cause which is creating the undesired effects.
      Anything else? :p
      RFB
    - March 25, 2012 at 5:21 pm #25449
      
      Carl Blare
      Total posts : 0
      Why does “clear clarity” make me think of wine? Oh, I guess because of “Claret” which fits that section of the vocabulary. I forget, is Claret red or white?
      Everything RFB has said throughout the CC project has been correct and I have tried and proved each stage of the process, which is why everything has worked as predicted.
      Even the kitchen radio is, yes, a drifter. Even being tuned to a solid signal that radio will drift and needs occasional re-tuning. Of course part 15ers love tuning things, so that is no annoyance. Once I picked up a Florida shortwave station at about 1mHz, middle of the AM dial, and I looked it up and it was a 1-million Watt station! But that never happened again.
      Since we managed to sink an 8-foot ground rod for this project, we certainly can get some outdoor antennas built. It would be nice to “put the RF out the door,” so to speak.
      AFTER THOUGHTS: Putting RF out the door sounds like we have a dog named RF. That made me think of the word “leash,” then my brain noticed that an antenna is not unlike a leash. How about calling it a “sky leash?”
    - March 27, 2012 at 1:56 am #25460
      
      Carl Blare
      Total posts : 0
      Another day on the CC with programs going out through the wall and across the poles.
      Because 2Watts works so well, I have the sense that more Wattage has no actual use in this setup, might even cause problems if we edged up to 20Watts (the max).
      But I would like to try less power, so we are preparing for a 1Watt test.
      You will hear all about it.
April 4, 2012 at 10:43 pm #25520

MICRO1700
Total posts : 0
I was telling Carl that there has been a real
lot going on here, and that I wouldn’t be on
the board too much right now. But here is
some CC stuff that happened.
I have all of the pieces together. The LPB
RC-6A is putting out 5 watts on 1020 now.
I changed some coil settings, and replaced
a questionable piece of coax that was going
to the watt meter. There still may be another
intermittent somewhere. I’m not completely
convinced yet that everything is right. But
it is good enough to proceed with the experiment.
The attenuator parts are on the circuit board. They
have to be soldered and connectors have to be
put on. I have the big wopping RC, and it does
tune to 1020.
I need a bunch of hours to solder, build, and
connect. But all of the pieces are there.
It’s just a matter of time.
One question for Carl – hey Carl – did you say
on a sensitive car radio you can hear WSM in
Nashville during the day? How cool is that?
Best Wishes,
Bruce, DOGGRADIOSTUDIO 2
- April 5, 2012 at 2:47 am #25521
  
  Carl Blare
  Total posts : 0
  Yes Mr. Doggradio 2:
  On many days and nights I can hear WSM from Nashville, and I treat that station with reverence because it is still doing what it classically always has done, broadcasting great country music.
  There are times when it does not appear on my radio, but more often I can hear it.
  As long as I am on here I will add a strange story titled “How Could That Happen?”
  Yesterday I was broadcasting as I have been recently at 670kHz, and everything has been fine.
  But this morning when I turned everything on, 670 had no audio. I was very confused at first, and began signal tracing.
  I found that the + wire on the audio input to the LPB transmitter had come loose and was sticking up in the air.
  Now, why did it stay connected during the previous days, yet come loose overnight?
  We may have to consult with Tha Dood and his house ghost (as heard on the Low Power Hour).
April 5, 2012 at 4:00 am #25522

MICRO1700
Total posts : 0
In the 21 years we have lived in our house,
I have heard strange noises in our kitchen,
which could not be explained at night.
But in all of that time, it has only happened
2 or 3 times. Just a “clunk.” For no reason.
But I don’t believe in ghosts, so it was probably
really the pipes, or something like that.
- April 5, 2012 at 5:04 am #25523
  
  MICRO1700
  Total posts : 0
  Here is a slight continuation of
  my message, because I had to
  turn off the computer, and catch
  a cab home from my job.
  That last (above) comment was made when I
  was waiting for the cab.
  Now I am home, so I can end the
  message.
  Best Wishes,
  Bruce, DOGGRADIO STUDIO 2
  - April 5, 2012 at 9:06 pm #25527
    
    MICRO1700
    Total posts : 0
    “It’s ALIVE IT’S ALIVE IT’S ALIVE
    IT’S ALIVE IT’S ALIVE HEE HEE HEE HEE”
    Frankenstein – 1931
    I put the my homemade CC coupler
    together and hooked it up.
    Power On.
    6 watts forward power.
    0 watts reflected power.
    (With LC tuned for best
    SWR.)
    Perfect SWR (Probably because of
    the 10 dB attenuator.)
    IT’S BLASTING!
    All over the house and up the street
    about 500 feet!
    I’M SCARED. I TURNED IT OFF!
    Bruce, DRS2
    - April 5, 2012 at 9:46 pm #25528
      
      MICRO1700
      Total posts : 0
      I turned it back on for a few
      minutes.
      All the resistors in the
      10 dB attenuator network were hot,
      so the network is working, I
      guess.
      Actually, i think my initial
      walk out was in the near field
      (maybe) I’m not sure. I had
      a really really good radio.
      So it may have seemed stronger
      than it really was.
      All the radios in the house
      are overloaded. Even the terrible
      clock radio up in the bedroom
      that doesn’t get anything.
      If you get farther down the
      street it seems to fade out
      in a linear fashion.
      I’m not sure what is going on,
      but I will call this a success
      because it’s getting SOMEWHERE.
      And as far as I know, nobody
      has tried anything quite like
      this before.
      Now I’ll have to figure out how
      well it’s really FUNCTIONING. In that –
      is my homemade coupler functioning
      in the same sort of manner as a
      commercial one.
      That’s going to be a difficult
      assessment.
      RFB. Let me know what you think
      when you get a chance. There are
      a tremendous amount of unknowns here.
      But it sure is a lot of fun!
      Bruce, DRS2
    - April 5, 2012 at 10:00 pm #25529
      
      Carl Blare
      Total posts : 0
      The 6-Watt LPB seems to be distributing its excess power evenly among the loading resistors, since you mentioned they are all warm, and because of all the overloaded radios in the near-field it sounds like your coupling is too efficient and needs to be “down-coupled” in some way.
      You did not mention hum in the carrier on the radio and that is a very good sign that you are able to get on the power lines without 60Hz hum getting involved with your carrier.
      One further test you should make is to visit the one or two neighbors so you can judge how well the signal is getting into their homes.
    - April 5, 2012 at 11:06 pm #25530
      
      RFB
      Total posts : 0
      “All the resistors in the 10 dB attenuator network were hot, so the network is working, I guess.”
      You may need to put a small fan on that to keep those resistors from thermally running away and changing value.
      “Actually, i think my initial walk out was in the near field (maybe) I’m not sure. I had a really really good radio. So it may have seemed stronger than it really was.”
      Near field indeed! However is your homemade coupler contained within a shielded enclosure and grounded at the TX’s ground potential?
      “All the radios in the house are overloaded. Even the terrible clock radio up in the bedroom that doesn’t get anything.”
      I think what is happening, since you have the load/attenuator inline taking 6 watts down to 600mW, your experiencing some RF leakage out of the coupler through the air. Again this depends on if the homemade coupler is shielded and enclosed.
      “If you get farther down the street it seems to fade out in a linear fashion.’
      Consistent with a far field effect, and normal for a CC’s near field effect if the signal is going down the length of the power line. The near field does not dissipate as quickly as a 219 setup does because our near field is being carried along the length of the power line, taking that near field down range along with the power line, whereas the 219 setup has a near field at the antenna and for a short distance, certainly not 500 feet. At 500 feet your in the far field on a 219 setup.
      Make sure that coupler is enclosed and shielded at the TX ground potential. Have the coupler as close to the injection point as possible (wall socket) so that the cord being used as the secondary of the coupler transformer is as short as possible. Also select an outlet as closet to the main breaker pannel as possible to avoid excess field emissions.
      I would not alter the coupler to “down-grade” it at all. You want maximum coupling efficiency and sounds like you hit the bulls eye right off. I would focus on the potential of emitted signal coming off the coupler device itself, chances are there is more signal being emitted directly from it than going into the power lines, and that would be solved with a well shielded enclosure and at the TX ground potential.
      “Now I’ll have to figure out how well it’s really FUNCTIONING. In that – is my homemade coupler functioning in the same sort of manner as a commercial one.”
      To see what the secondary side is doing, you will need to build and install an SWR bridge on the output side of the coupler so you can see exactly what kind of VSWR there may be going into the power grid. This can also cause the overloading issue if the VSWR is considerably high. You may see a low VSWR on the coupler input side (primary) but on the secondary, without a way to bridge it and measure it, there is really no way of telling how that side of the coupler is working.
      RFB
    - April 5, 2012 at 11:50 pm #25532
      
      MICRO1700
      Total posts : 0
      The coupler is on the test bench.
      It is not shielded – but it will
      be (somehow!)
      The set-up is on the first floor
      of the house and not the cellar.
      The set-up is grounded to the
      radiator in the room.
      This is not the way it want it
      to be, but I wanted to see if
      it worked at all, and it seems
      to.
      So the changes will be made as soon
      as I can.
      Thank you so much for your note!
      I’ll be getting back to you.
      Bruce, DOGGRADIO STUDIO 2
    - April 5, 2012 at 11:57 pm #25533
      
      kc8gpd
      Total posts : 0
      my trip to rhoadescar factory in Tennessee stopping at 650 am wsm nashville
      https://www.facebook.com/media/set/?set=a.110466425659118.5851.100000872822280&type=3&l=e0e17853bb
    - April 6, 2012 at 12:29 am #25534
      
      Carl Blare
      Total posts : 0
      The pictures from WSM are really good to see. What an impressive looking tower they have.
      On a comment made by RFB on the “Scored Again” thread I got a whole new idea.
      My house is the last house on the power transformer which feeds the lines being used for my CC operation, and all the houses eastward are on the same line.
      But the house right next door on the west is on a different transformer. I know this because when I have a power failure they don’t, and when they have a power failure I don’t.
      So, if I could get a drop from that other nearby transformer, I’d end up with two electric meters, and I’d be able to feed CC to a whole additional row of homes.
      But of course it would be necessary to use a different frequency to avoid cross-talk interference, right?
    - April 6, 2012 at 12:39 am #25535
      
      kc8gpd
      Total posts : 0
      in my opinion wsm 650 is the last of real radio on a licensed station in this country. and one of the very few am’s who take care of their am facilities and i believe the only one with a blaw knox fed by a ladder line feeder
    - April 6, 2012 at 1:13 am #25536
      
      RFB
      Total posts : 0
      “So, if I could get a drop from that other nearby transformer, I’d end up with two electric meters, and I’d be able to feed CC to a whole additional row of homes.”
      Usually the utility won’t do that for various reasons. Each grid or blocks of grids will have their own neutral off those step down transformers. A high probability of voltage potential may exist between those two or more neutrals in reference to Earth ground.
      Solution here is to run a power splitter (RF) and feed two couplers. If the next door neighbor is willing, install the second coupler on their breaker panel including installing an isolated Earth ground rod and there you go. The coupler itself provides the isolation because no where within the coupler does the input have direct connection to the output.
      “But of course it would be necessary to use a different frequency to avoid cross-talk interference, right?”
      No.
      RFB
    - April 6, 2012 at 2:16 am #25537
      
      Carl Blare
      Total posts : 0
      It is valuable to learn about the hazard involved with having two different electric feeds from different transformers, because of yet another reason why I’ve thought about that other feed located just next door…
      When those power failures occur I have often looked next door and there they sit with lights and heat and refrigerators humming….
      On the other hand when I’m the lucky guy I have thought of handing an extension cord over the fence as a neighborly gesture, but now I know better. Not such a good idea.
      As far as putting a coupler at their panel, that is an interesting thought. What we need is something to barter so they get some benefit out of it. I’ll be busy thinking about that.
    - April 6, 2012 at 5:55 am #25538
      
      MICRO1700
      Total posts : 0
      Carl! Somehow I missed your comments. Thank
      you for letting me know what you thought.
      And Carl, I may have a similar situation
      as yours. I believe my house is not on
      the same circuit as some of the other
      nearby houses. I’m not completely sure
      about this, but during that big storm
      in the fall, a lot of houses lost power,
      and so did we. But a lot of houses got
      power back before we did. We are on a
      main street, and might be at the end of
      one grid and the beginning of another.
      No matter. I am very happy with the
      experiment so far. There is very little
      hum on the radios in the house, also.
      Before I say more, I want to put in a
      plug for the wonderful pictures of WSM
      from Robert, KC8GPD. I too, think a lot
      of WSM. It is a very very special radio
      station.
      Back to my CC experiment. There is some
      RF coming off of the LC network. But
      my cruddy little CB/ham field strength
      meter has given me a few clues. There is
      not nearly as much radiation coming off
      the LC as there was from my Part 15.219
      three meter stick. In fact, there seems
      to be quite a bit less, although there
      is right now no way to convert that to
      meaningful data.
      The uniqueness in this approach is the RF
      attenuator and the fact that the extension
      cord is just wrapped around the LC. (This
      is the extension cord that is feeding the
      CC transmitter.) And for those of you who
      haven’t seen too much writing on this
      experiment, (I’m going to say this loud.)
      THERE IS NO DIRECT ELECTRICAL CONNECTION
      FROM THE TRANSMITTER/RF ATTENUATOR/LC CIRCUIT
      TO THE A.C. LINE! That’s important to remember.
      Again, the AC cord feeding the transmitter is
      just wrapped around the big LC.
      I just realized I can take the AC cord feeding
      the transmitter out of the line and feed power
      to the transmitter from another extension cord,
      with everything else remaining the same. This
      MIGHT provide some clues as to how much RF is
      coming out of the coil and how much is going
      into the AC line. I might be able to get some
      clues by making this change.
      Shielding the RF attenuator network is no
      problem. I have metal enclosures for that.
      That LC is another matter, though. That
      will be a lot harder. It may come down
      to a box wrapped in aluminum foil and grounded
      to TX ground.
      By the way, I was just barely able to construct
      this thing. My eyesight was not good today.
      However, the experiment came out pretty good and
      I was able to check everything appropriately
      before I powered the thing up.
      When I put this in the cellar near the breaker
      box, there will be no way I can put a metal
      pole into the ground. It is my figuring that
      connecting the TX ground to a water pipe is
      OK. The reason I say this is because the
      TX is FLOATING ABOVE GROUND. I hope this
      makes sense.
      IF ANYBODY ELSE TRIES THIS, REMEMBER THERE
      IS NO DIRECT CONNECTION FROM THE TRANSMITTER
      RF OUT TO THE AC LINE! IT IS ALL JUST COUPLING!
      I DON’T WANT TO SOUND LIKE A LOUD MOUTH, BUT
      I WANT THIS TO BE CLEARLY UNDERSTOOD!
      OK. I’m done yelling now. By the way, I am
      an almost legally blind dude with very little
      engineering experience. And although I have
      done a small amount of radio engineering work
      it was just a little years ago.
      So if I walk into the other room and this thing
      starts smoking and blows up, you will know that
      I messed up somewhere.
      Thanks for reading this!
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 6, 2012 at 11:17 am #25539
      
      MICRO1700
      Total posts : 0
      Hi, I’m Mr. Loudmouth. I yell a lot.
      Well, not really. I just put those
      comments in the last post in caps so
      nobody gets slightly killed – if they
      try my CC experiment – but don’t
      completely understand what is going on.
      Ahem.
      Seriously, in reference to WSM. There
      are some great things about that radio
      station. There is a live person there
      all night playing music. What other
      clear channel AM station does that? I can’t
      think of any. And it comes in great
      here in Connecticut at night.
      I decided to listen to it last night as I
      was drifting off to sleep.
      As a struggling jazz musician (I used to
      be pretty good) I can appreciate just about
      any kind of music – because music is hard
      to make and have it be good. You have to
      know what you’re doing. So even though
      county music isn’t what I usually listen
      to – there was a lot of really great music
      on WSM last night. Really good stuff. Both
      new and classic country.
      If you look at Radio-Locator.com you will
      see how interesting the 650 channel is at
      night. In the U.S., Canada, and Mexico
      there are 26 stations on 650. A few of
      those stations go off completely at night.
      A lot of them drop to very low power. And
      even some that are very far away from
      WSM fire their pattern away from Nashville.
      As I was listening to WSM last night, I
      turned the radio to a different direction
      and DID get another station on 650. I think
      it was Spanish language. However, before the
      top of the hour, the unknown station faded out,
      so I was unable to get any kind of ID.
      One of the WSM IDs mentioned that they have
      been pretty much been the same for 86 years.
      How wonderful is that?
      I think I’ll listen to them more at night.
      Again, Robert, KC8GPD, thanks for the
      great photos!
      Bruce, DOGGRADIO STUDIO 2
    - April 6, 2012 at 5:28 pm #25543
      
      MICRO1700
      Total posts : 0
      I have some good news and some
      bad news, but first I will tell
      you about this morning’s experiment.
      I turned the CC set-up on and went
      for a walk around the block that
      is opposite my street. I heard
      the signal the entire way. Completely
      around the block.
      Then I unplugged the transmitter A.C.
      cord from my homemade coupler and just
      plugged it into an outlet strip. Then
      I went for the same walk around the same
      block across the street.
      At first I thought there was no difference.
      But then I got out of what must have been
      the near field.
      The signal was not present around that block
      across the street. It wasn’t there.
      So, I guess this shows that the coupler really
      is coupling. In other words, it’s working.
      That’s the good news. Now here’s the bad news.
      I am getting a 10 kHz hetrodyne from a New York
      station all around that block. I had thought
      the signal from 1010 New York wouldn’t be that
      strong. Maybe this is just a good day for
      daytime ground wave and skywave? Maybe the
      D layer is not that oppressive today?
      But – and this is the bad news – I don’t think
      I can use 1020. I’m not sure anyway.
      So I came back to the transmitter. It is
      running without the coupler going anywhere.
      It is just running into the attenuation
      network and the LC, and the LC secondary.
      And of course, the LC secondary is not
      connected to anything.
      There is no RF field coming off of the
      LC coupler now. The resistors on the
      attenuation network are pretty hot.
      The SWR in still unity. So i guess the
      resistors are now taking all of the
      power, and maybe some of the field is
      coupling to my outside antennas, or
      other wiring, I guess.
      I guess I’s better turn it off before
      those resistors get too hot.
      So, the experiment worked pretty well.
      But, I guess I’m still on the wrong
      channel.
      Best Wishes,
      Bruce, DRS2
    - April 6, 2012 at 6:02 pm #25544
      
      Carl Blare
      Total posts : 0
      At first I didn’t post about Doggstudio 2’s technical findings, for the very reason that all I was doing is thinking about it. I wasn’t sure about what I could say, and it makes very little sense to come on here with nothing but silent thoughts. But there was a clicking noise and all at once I know what to say…
      Bruce, your experience with the NY station at 1010, exactly next door to you at 1020, is a perfect match to my reason for NOT going on 660, which would have been great, EXCEPT that it was right next door to 650, WSM, which we have mentioned.
      In your case you happen to have a 1020 crystal, which is why you ended up on 1020. In my case I never had a 660 crystal, so I was able to make a choice. In your case, (if I recall correctly), you were given a crystal that already was 1020, and you did not have a choice.
      Probably the toughest part of carrier current is getting the right crystal and then tuning the transmitter for the right part of the band.
      Building a PLL frequency selector would solve half of that problem, as RFB has so well discussed.
      But of course, once you get established at “the right frequency,” you may never need to change it again.
      Having kids is much simpler.
April 6, 2012 at 7:42 pm #25547

MICRO1700
Total posts : 0
Well, it’s always nice to hear from you!
Yes, we are sharing the experience of not
being on the right channel.
For me, 1020 is great if the signal is
just in the house. So I will go back
to my leaky coax set-up in the house.
And I will look for another way to
get onto another channel.
What channel and how will I get there?
It doesn’t matter. The coupler experiment
worked and that makes me happy.
Always good to hear from you.
Bruce, DRS2
P.S. Yup, I think having kids IS
simpler.
There is one other thing. The PLL
exciter going into the crystal socket
is great, and I might do that. BUT
in this particular transmitter, I
believe modifications will have to
be made to the crystal osc. circuit for it
to be driven by the PLL.
We’ll have to wait and see if RFB
has any take on this. I’m sure he will.
- April 6, 2012 at 7:52 pm #25549
  
  RFB
  Total posts : 0
  As I noted before, an LC equivalent circuit with a varactor diode (preferable double-ended) to replace the crystal element, then controlled by the PLL.
  Not going to be easy without a roadmap to the unit, but not impossible.
  RFB
April 6, 2012 at 9:13 pm #25551

MICRO1700
Total posts : 0
Yup! Well, my friend, we will just
see how it goes.
Best Wishes,
Bruce, DRS2
- April 6, 2012 at 9:22 pm #25552
  
  RFB
  Total posts : 0
  First thing is to create an LC circuit which will run the tube’s oscillator section. Once that is done, add a varactor to the tank (double back to back varactor for finer tuning).
  Google crystal equivalent circuit for many examples.
  RFB
April 6, 2012 at 11:09 pm #25553

MICRO1700
Total posts : 0
I’m already looking.
This is very very interesting. But whatever
I do, it will take a while.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- April 7, 2012 at 2:04 am #25562
  
  Carl Blare
  Total posts : 0
  So here I am thinking again and reflecting back on the fact that the auto radio stops hearing AM 670 CC at about 2.5 blocks. I am guessing that the power line off of my transformer or perhaps the neutral line from my electric service ends at that spot, running into the ground for the last time.
  But what about next door to that?
  What about a few more homes beyond that point?
  Is anything getting into their power wires that might be me and my signal?
  - April 7, 2012 at 2:08 am #25564
    
    RFB
    Total posts : 0
    “What about a few more homes beyond that point?”
    The next step is to take a decent portable to the next power pole beyond the 2.5 block drop point, walk up to it with the portable and see if the radio starts picking up the signal within 1 to 3 feet. If it does, your signal is getting further down the line past the 2.5 block point and into the other homes.
    RFB
- April 7, 2012 at 2:24 am #25565
  
  RFB
  Total posts : 0
  “This is very very interesting. But whatever
  I do, it will take a while.”
  Hi Bruce!!
  Well there isn’t any deadline that I am aware of! 😉
  The roadblock here is that the RC-6A uses the same tube for both the oscillator and modulator/final. And adding even more difficulty is the unit has no power output adjustment so experimenting with the front end of that tube (oscillator) while it’s also performing amplification will make things a bit more difficult. When it’s time to test the LC circuit for in-band oscillation, use the regular dummy load on the output and not the new resistor load/attenuator stack.
  Well I wouldn’t call it a roadblock..but perhaps a speed bump so we will have to slow down anyway and take our time! 😀
  Besides..there is a speed trap past the first block! 😉
  RFB
  - April 7, 2012 at 12:49 pm #25569
    
    radio8z
    Total posts : 0
    There is a lot of information contained in this thread, almost too much to wade through and absorb.
    RFB, would you consider writing and posting a Carrier Current Primer with basic information all in one place for those who are considering CC? Perhaps a generic presentation on the fundamentals?
    Neil
April 7, 2012 at 4:03 pm #25571

MICRO1700
Total posts : 0
Hi Neil! And while we’re waiting for RFB to
answer Neil’s question – I have some more
CC test data to post.
Maybe 1020 isn’t such a bad channel at all.
I’m beginning to think the interference I
heard yesterday was from something else. 1020 might
be OK. I thought it was a het yesterday from
a station down one channel, that I
heard. However, it didn’t seem to be there today. (???)
I’ll have to check again later.
In any case, I’ll just post the findings of my
experiment.
I turned the transmitter on this morning,
and tuned for
lowest SWR again. I was on my way to work,
so I set a timer so the CC transmitter would
go off in 15 minutes.
After we finally actually got into the car, we
drove around some adjacent blocks, that come
up against the other side of my street.
I was surprised to get reception on the car radio
3 blocks down and 3 blocks over. So we drove
around all nine blocks in the three by three area.
The signal was there around all of the nine
blocks! This really surprised me! So the signal
was not very strong – but it was in ALL of those
areas. We started to go out of that perimeter to
investigate if there was further coverage. But at
that point my digital timer at home turned the
transmitter off. (All of the blocks travelled had
power lines all around them.)
So it looks as if there is a nine block coverage
area at least.
I am finding it very very interesting that the junk
box coupler I built is doing this. I find it hard
to believe, but it seems to be true.
As many of you have read – RFB is advising me how
to rig an external PLL to run the transmitter on
a wide range of frequencies, and I will be looking
into that.
However, 1020 may not be so bad after all. I’ll have
to do a bunch of tests over a period of time.
I also know somebody who has a 970 kHz crystal
that I might be able to get. 970 is empty here
during the day. It might be something else to
try if I can get my hands on that 970 rock.
I also have some oddball crystals on the AM band
that are not on good channels. But it might be fun
to grind them in order to raise their operating
frequencies to something I might be able to use.
Crystal grinding
is not a lost art. There are still people doing it.
My eyes are limited, but I don’t think it takes too
much sight to grind a crystal, and besides, I
have nothing to loose anyway.
Well, that’s my report. Again, this is really really fun.
To me, it’s like a whole new world to investigate.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- April 7, 2012 at 6:30 pm #25573
  
  MICRO1700
  Total posts : 0
  Hi Guys:
  My previous post talked about the
  coverage coming from the power lines
  around a 9 block area. Well, I’ll have
  to check the map again, but now we
  are looking more at like 12 or 15 blocks!
  (This would be in a 3 block by 5 block
  area.)
  This is NORTH of my street. Here’s the
  interesting part. Unless my map reading
  is wrong, there seems to be very little
  coverage on the SOUTH side of my street.
  This must be the way the GRID goes! (Or
  doesn’t go!)
  Yikes! This is SO INTERESTING from an experimental
  standpoint!
  My mind is still having trouble comprehending the
  fact that, the signal will be stronger(?) inside these
  houses, where radios are plugged into the AC outlets.
  If the radio has a transformer – will that stop the
  signal, or will the signal just sort of leak past the
  transformer?
  And what about battery powered radios that are placed near the
  AC outlets? How will they perform?
  And the strength of the signal – it is weak along the
  whole route, and roughly the same strength, until you get
  over to the north side of the 3 by 5 block perimeter.
  Then the signal is a little weaker.
  Here’s what I don’t understand. The transmitter is not
  near the power panel yet. The LC set-up doesn’t seem
  to be putting out much field strength, certainly not
  after the near field. The set-up is on the TEST BENCH on
  the first floor – not in the cellar. And the transmitter
  ground is connected to the radiator. Are the pipes
  radiating, too? If that is so, then I must get this
  thing downstairs right away. And I am really not in the
  position to put a ground rod in. (The explanation
  for that is a long story.) The plan is to have the transmitter
  float above ground (from the house wiring) and ground
  it to a water pipe in the cellar. The plan also is to have
  the transmitter fed by an FM tuner (like Carl is doing.)
  The FM tuner will be tuned to the DOGGRADIO FM
  Part 15.239 channel. The FM tuner will also float
  above the house wiring ground..And the resistor attenuator
  network and the coupler LC will be shielded.
  I’m concluding these short tests for now. The hardware
  will have to be moved. I DO NOT want to do anything
  wrong.
  It still surprises me that this Carrier Current thing seems to be working.
  It’s just like nothing I’ve ever seen before. New territory.
  And I don’t want to run it until I really understand what’s
  going on.
  Best Wishes,
  bruce, DOGGRADIO STUDIO 2
  - April 7, 2012 at 7:18 pm #25574
    
    Carl Blare
    Total posts : 0
    Doggradio2 seems to have the “Midas Touch,” his CC experiment turned to gold right away.
    Based on how well it’s working I think you can leave the equipment where it is, unless you need to move it for other reasons.
    Refinements lie ahead including building the Standing Wave (SW) detector.
    The questions you asked can be answered somewhat by what I am finding with my CC setup… power transformers in the radio don’t matter…. the RF energy is there and it jumps to radio reception both to AC plug-in sets and portables.
    If there is a friend in the outlying coverage area perhaps they will allow you to stop by for an indoor reception test.
    Once you declare the experiment concluded and have a definite system, I hope you might draw the diagram of how it works for posting here on the site.
    The exceptional thing is that your method avoids ever handling high power wiring. The safer the more pleasing it can be to users in the future.
    If I were you I would tell all your easter friends that you are an acclaimed inventor of a new radio coupling method. When they start asking what that means, do your thing of saying you’ll get back later.
    Perfect!
April 7, 2012 at 8:47 pm #25576

MICRO1700
Total posts : 0
Well, your words are very kind and
always good to hear!
The signal on the car radio IS weak.
It sounds like the old DOGGRADIO 1690
Part 15.219 100mW DC in, 3 meter stick –
as heard a mile or two away. And our
car radio is very sensitive, so I wonder
if a regular portable radio under the
power lines would even hear the transmission.
This does make me think that I am
probably not violating the RF field strength
formula/regulation for the power lines.
Then my mind still has to grasp the
fact that, in the houses, at the A.C.
outlets, the signal will be strong
enough to listen to clearly.
I will eventually get into a friend’s
house on the grid to check. But these
people have busy lives, and even though
they know I am a real radio guy, and
not a crazy nut, this will still have
to be done in a low key way.
Thanks again, Carl and best wishes,
Bruce, DRS 2
P.S. And you’re right about relating to
other people about this thing. Nobody
understands it. But my wife was kind
enough to drive me around. (Then again,
i don’t completely understand it either.)
- April 7, 2012 at 9:01 pm #25578
  
  RFB
  Total posts : 0
  Interesting idea Neil. I may consider doing that and submit it for entry in the resource library.
  The newest CC system/experiment…let’s not get too ahead of things just yet.
  Once the LC/Coupler circuit is enclosed and shielded and checked for RF leakage, it cannot be ruled out that it’s acting like a transmitting loop with some coupling going into the AC lines via the extension cord. Adding the system’s location (upstairs) could also add to the results your getting.
  The only ground involved here is the TX ground potential tied to the radiator. It won’t radiate, but could be getting strong near field induction from the LC loop and embedding the signal onto that and other pipes within the home, in turn making them radiate.
  It’s too early to really tell how well the custom coupler is actually doing it’s thing while it is in the open, unshielded and with no SWR bridge across the output. So far the primary of the LC is tuning up ok with low VSWR, and that is good for the TX’s sake in seeing a constant load impedance. But that could change a little with more or less inductive coupling on the secondary..ie more wraps of the extension cord around the form, or less wraps.
  In all I believe your experiencing a little of both CC and emission right off the LC loop itself, and a third effect, the strong near field inductive coupling to nearby wiring and/or piping coming off the LC loop since it is unshielded.
  Your on the right track. Conduct the tests again after enclosing the custom coupler and moving the system to where you intend to have it for normal operations. As Carl found out, being away from the breaker panel didn’t work out too well until moving the whole setup right next to it. And you will want to be right at the breaker panel so as to make the coupling link (extension cord wrapped around the LC form) to be as short as possible to maximize the coupling onto the grid lines.
  Another thing to remember is CC is an inductive system and works with the near field and very little far field. It takes less than a half watt ERP off the grid to obtain the needed near field strength to make the CC system viable. Since the grid lines are very low impedance, and since the CC system relies on inductive coupling onto the grid lines, it takes a little RF power to get to that half watt ERP off the grid lines. Depending upon the overall load factors on the grid lines, and it’s load impedance, often only a watt or two up to 5 or 10 watts (TX RF output) is sufficient for an effective CC system.
  Also remember the goal is NOT obtaining a long far field!!! 15.221 does not allow for a long distance far field!!! CC systems are not measured in the far field!!! If the CC system is working properly, that signal will drop like flies at the 157000/F distance, which is the noise floor or 15uV. This is not easy to measure when you have a cluster of power grid lines at every half block or full block. But the signal will not fade gradually, or linearly with increased distance from the lines. It should drop suddenly, like hitting a brick wall.
  RFB
  - April 7, 2012 at 9:24 pm #25580
    
    MICRO1700
    Total posts : 0
    Within my limited experience, everything you
    are saying makes sense to me.
    I will check your formula with the near field
    “RF falloff” and see what’s up there. If I
    am not understanding – just bear with me.
    I will do the checks regarding the formula
    and Part 15.221. (My eyes are not cooperating,
    so I have to keep reading this stuff over
    and over.)
    I agree with everything that you say I need
    to do. It will not be easy to get close to
    the breaker panel – it is right behind the
    furnace. But I’ll see what I can accomplish.
    This is really foreign to me. I’m glad (and I’m
    sure a lot of other people are also) that you
    are here!
    Now I’m going to step back and take a good long
    hard look at this thing – and reread your posts –
    and a bunch of other related information.
    I can’t thank you enough!
    Bruce, DOGGRADIO STUDIO 2
    - April 7, 2012 at 9:28 pm #25584
      
      MICRO1700
      Total posts : 0
      I just read your last post again.
      I think I’m getting the idea now.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 8, 2012 at 1:46 am #25592
      
      RFB
      Total posts : 0
      A good way to determine the drop off point is to use a small 9 volt powered AM radio and move away from the line till you reach your 157k/F point. At about 15 feet before reaching that distance point the signal should begin it’s change from near field to far field. Around 8 feet it will seem like picking up a 219 stick with an 80/20 signal to noise ratio (aprox) and drop sharply as you approach the distance point.
      Ex: TX Freq-710Khz
      157k/710=221 feet aprox. drop off start 216
      (meter formula)47715/F
      47715/710=67 meters aprox. drop off start 65 meters
      RFB
April 8, 2012 at 6:32 pm #25603

MICRO1700
Total posts : 0
From what you say, I don’t think
I was that far off the mark regarding
the transition from near to far field.
As far as distance from the transmitter
is concerned. Of course, without measuring
the distance exactly it’s hard to really
know for sure. But the change over point
from near field to far field isn’t drastically
off, anyway.
BUT SOMETHING BROKE AND IT DOESN’T WORK
ANYMORE. RF and SWR readings are off, and
the LC won’t peak.
No matter. It’s an experiment and I’m having
fun anyway.
I hope I can get it back to the way it was before.
Then we’ll go on from there.
I can’t really see the words on this laptop I’m on –
but I’ll be back.
Best Wishes, Bruce, DRS2
I still can’t believe it worked
in the first place. (Or – worked
as well or poorly as it did.)
- April 8, 2012 at 8:25 pm #25610
  
  Carl Blare
  Total posts : 0
  How could we jump all at once from everything working beyond expectations to something being broken and not working anymore?
  There must be an in-between moment when something happened that might explain the change, like Hoover the dog chewing on the LC or the neighbor from clear channel doing a jamming signal.
  Give us a theory to work with.
April 8, 2012 at 8:35 pm #25611

MICRO1700
Total posts : 0
Hi RFB! We’ll I’ll have to
take the whole thing apart
and start over, in order to
trouble shoot it, but again,
to me this is all fun!
I used your formula for 1020 kHz.
The distance came out to about
150 feet for the near field.
Conveniently, the property
lots on my street are about 75 feet
wide. So, looking back at walking
out of the house with a radio a
couple days ago – I’m trying to
remember when the strength fell off
like a cliff. I do think it was
before 150 feet, based on the width
of the properties as I walked down
the sidewalk.
This is a very cool experiment.
Best Wishes,
Bruce, DRS2
April 9, 2012 at 6:14 am #25620

MICRO1700
Total posts : 0
Hi Guys!
I took the experimental carrier current
coupler apart and put it back together
again.
It is working now.
There is a field coming off of the coil.
RFB is right. This cannot be used unless
it is near the breaker box and shielded.
Now I know why people look for commercial
couplers. If you can get one, it’s just
plain easier to plug it in and have it
work.
However, I am still drawn to this experiment
like a magnet. I find it to be very interesting
and I am learning more. Learning more about
RF and RF circuits. As someone who was never
a real RF engineer, there is a lot of interesting
radio theory coming together in my head.
Yup, it is still a lot of fun. I might build another
10 dB pad (or more) and put it in the
line. That way the
power going into the coupler will
only be 50 mW (or less)
That will probably pass the field strength regs
for the near field. Then I can just observe
and experiment, and figure out how to shield
this thing. (And listen to this wonderful
antique transmitter in the house without
worrying about being in violation.)
The experiment in it’s present form is over. It
cannot be used this way.
Bruce, DRS2
- April 9, 2012 at 1:57 pm #25625
  
  Carl Blare
  Total posts : 0
  Your experiment was exactly what a good experiment is…..informative and instructional….. you have learned from it and can now plan a better experiment, Doggstudio2.
  Because I am getting such good results from only 2-Watts, I am not surprised that you are finding it necessary to dump much of your Wattage.
  What I suspect is that LPB and now Radio Systems found that having a variable power transmitter is necessary to deal with the extreme variation of results from different power-line situations.
  On the one hand it seems undesirable to change a legacy device such as your 6-Watt transmitter, but on the other hand modifying it with variable power makes a lot of sense, and perhaps you could engage Mr. RFB to design the modification.
  - April 9, 2012 at 8:26 pm #25633
    
    RFB
    Total posts : 0
    There is a modification for the RC-6A to have variable power. I just can’t remember certain specifics, but it involved adding a variable biasing voltage somewhere in the final circuit. I had the notes to the modification and circuit diagram and circuit modifications on the stock unit. Unfortunately those notes cannot be found.
    A schematic of the RC-6A would be helpful. Again unfortunate that I no longer have the manual and schematic to the RC-6A either. TIS what happens when you move several times across several states and cities over a 35 year period!
    RFB
    - April 9, 2012 at 9:48 pm #25637
      
      MICRO1700
      Total posts : 0
      I’m on my daughter’s laptop, which
      I can barely see, because the screen
      is too small, even if I wear magnifying
      goggles. I cannot get the mag
      software to run.
      I appreciate your input, RFB and Carl!
      I’ll be back here from the “nice big”
      computer later on. My wife is watching
      TV shows on it. (She works really hard
      and deserves to watch fer stuff.)
      As you know, the Doggradio computer went
      down.
      So thsnnkd you guyd snf I’ll be back as
      soon as I can.
      Best wishes
      Bruce, drs2
  - April 9, 2012 at 11:04 pm #25638
    
    RFB
    Total posts : 0
    “What I suspect is that LPB and now Radio Systems found that having a variable power transmitter is necessary to deal with the extreme variation of results from different power-line situations.”
    You are correct. In early CC history and for the typical setup situations (dorms etc), and because of the less than optimum coupling techniques and gear around at that time, power level adjustment was not really an issue. But with the far better couplers it became clear that power adjustment was needed to ensure compliance as well as prevent close proximity receiver saturation issues.
    As you have discovered, it does not take a whole lot of power to get the signal down the line. It is a balancing act between good coverage and prevention of receiver saturation and interference issues, thus without the ability to adjust that power level, the balancing act would be impossible.
    RFB
    - April 10, 2012 at 3:37 am #25645
      
      MICRO1700
      Total posts : 0
      We’ll, all I can say about these
      makeshift carrier current experiments
      is that – in the few days I ran this
      experimental setup – I had one of
      the most wonderful and perplexing
      experiences I’ve ever had in Part 15
      radio or any radio for that matter.
      (B.R.O.S. – Big Run On Sentence.)
      There is no way to get any meaningful
      data unless the experimental set-up
      is shielded. Also, it had been moved
      around on the test bench, and that might
      have changed the results, too.
      I do not have the eyesight to go poking
      around inside the RC-6A unit. (At least
      not right now.) But building attenuators
      is easy. Even I can do that.
      I am not done with this thing, but I am
      at a temporary wall now.
      RFB and Carl – thanks for all of the great
      comments!
      Bruce, DRS2
April 18, 2012 at 12:08 am #25755

MICRO1700
Total posts : 0
Hi Guys:
As you know, I’ve been experimenting
with carrier current. I have been
using a 1971 LPB RC-6A transmitter
and a homemade coupler that couples –
but doesn’t have a direct connection
to the power line.
These experiments will continue when I
can shield the homemade experimental
coupler.
A great friend here in town who is a
broadcast engineer has a commercial
coupler. He will be lending it to
me probably in the not too distant
future.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
April 18, 2012 at 11:10 pm #25760

rock95seven
Total posts : 0
and why not?
I am playing around with carrier current as well but here is where i have to do things differently. Aside from Rock 105.3 FM station radiating on a home made folded dipole i also have a Sstran broadcasting on 800 AM using the shield side of 50 feet of 75 ohm coax. The AM signal is limited range i guess about 30 feet from the house before the signal dies out. That AM signal is intentionally limited as it was only meant to be an experiment to limit the signal to my house only.
Now here comes the part where i am doing things differently.
I have resurrected the old frequency of 95.7 fm by wrapping a length of wire measured for said frequency and wrapping that around the extension cord and grounding the transmitter to a separate ground outside. I tried this without the ground and was hearing a hum in the audio but it was not AC hum, i suspect it was a ground loop of sorts since it sounded much like the hum or buzzing you hear when you have a bad audio cable.
After connecting the ground the hum was gone. The transmitter I started to use was the Ramsey FM 25b but 25 mW did not seem to go much further than the mobile home park over a car radio and a Grundig portable shortwave/Am/Fm Radio. Reception was better on the car radio than it was on the portable but if you put the Grundig close to one of the many lamp posts’ in the park the signal was there so i have every reason to believe this is working. At this moment I am using a Mobile Blackbox V6000 which is adjustable to 200 mW and mono. I see a bit more improvement at 100 mW. If i keep the CC FM going it will just re-broadcast what is going out on Rock 105.3 FM.
It does seem to me that anyone could listen in their mobile home if their radio was plugged into or was close to an outlet or wall. I have been pretty busy with some family business that is more important than radio at this point but my plan is to take my Grundig G3 to a friends house on the other end of the mobile home park, plug the radio in and see if any signal is making it into his home.
Whatever the CC FM won’t cover the transmitter on the folded dipole should fill in those dead spots if anyone is listening to it on a car radio.
More later.
- April 18, 2012 at 11:51 pm #25761
  
  MICRO1700
  Total posts : 0
  It’s always nice to hear from you!
  Well, I don’t understand the theory
  side of what your doing, but I guess
  as long as your RF radiation is within the
  rules you’re good to go.
  My mind is a little foggy. Are you the
  person that’s starting the network, or
  have I got the wrong guy? I guess my
  mind is really foggy.
  Best Wishes To You, Barry
  Bruce, DOGGRADIO STUDIO 2
  - April 19, 2012 at 1:22 am #25762
    
    mram1500
    Total posts : 0
    Well, it seems I’ve been operating a 160 kHz carrier current station for some time now and wasn’t aware until this evening.
    My Realistic Plug’n Talk FM Wireless Intercom operates at 160 kHz with 75mW RF output. I always figured it to be a little further up the band.
    So, I have the distinction of operating an LF FM CC station.
    Programming has been dead air except for occasional ambient sounds and noise I make when working in the garage.
    I keep the transmitter on to monitor happenings in the garage like the occasional racoon that wanders in.
    I have not received any RECEPTION REPORTS yet but I have QSL cards ready – just in case.
    - April 19, 2012 at 2:16 am #25766
      
      Carl Blare
      Total posts : 0
      I am wondering, MRAM, since the serious CC rule only covers 530-1700kHz, why is the intercom device legal? Maybe like the raccoon, you are a bandit wearing a mask.
      Obviously I am being silly with that, you and the raccoon are simply in the proximity of a LW operation.
      I just skimmed through the rules looking for the power limits that apply in general, prior to the sections granting special “intentional radiator” limitations, but it made me dizzy.
    - April 19, 2012 at 10:48 am #25771
      
      RFB
      Total posts : 0
      Why wouldn’t it be legal?
      Does CC only mean CC applies to the MW band?
      Why would CC be considered non-compliant on another band besides MW?
      For decades there have been such devices like baby monitors and intercoms using CC. As long as those devices in the 160-190Khz band operate with the 1 watt power input limit, it don’t matter if your coupling to a 50 foot pole or the power grid.
      There is nothing within the rules anywhere saying that CC shalt not be used on any band other than MW.
      RFB
    - April 19, 2012 at 7:42 pm #25776
      
      mram1500
      Total posts : 0
      Agreeing with RFB, I suppose Radio Shack submitted the device to the FCC and they said OK.
      The power companies use CC on the high voltage power transmission lines to monitor and control the grid. There are lots of consumer products that use CC; things like remote control switches and outlets, telephone extensions over AC lines, etc.
      Hey, maybe I could convert these intercoms from CC to FREE RADIATE. Let’s see, 75mW into a 50 foot antenna…
    - April 19, 2012 at 8:07 pm #25777
      
      Carl Blare
      Total posts : 0
      Everything being said regarding the baby monitor type of CC has been digested in my brain’s sausage packer, and I wonder the following:
      How can the AC power line be tapped by the antenna input of a LW radio to scan for neighborhood baby monitors?
    - April 19, 2012 at 11:37 pm #25778
      
      mram1500
      Total posts : 0
      I would guess the same way RFB has told us to just get the radio near the AC line. The signal may be strong enough to radiate to your LW radio.
      Perhaps simply wrapping a few turns of the antenna wire around an AC cord would do.
April 20, 2012 at 12:37 am #25779

rock95seven
Total posts : 0
Years ago when i was in high school an old friend of the family installed those great light switches, outlets and other modules for indoor & outdoor lights. From his armchair he could use a remote control just like a t.v. remote and turn on and off lights,a radio or control outdoor appliances like the light above the barn. The remote receiver could also be programmed to turn things on and off at set times during the day or night.
The cool thing about it, yep it was carrier current. Not sure what channel or band it was on but it was really cool. I think X10.com or another company whose name escapes me uses the same principle to remotely control devices around the home or office.
- April 20, 2012 at 1:34 am #25780
  
  Carl Blare
  Total posts : 0
  Rock95seven you may have provided the answer to my question of how to remote control several transmitters, especially the CC transmitter way down deep in the basement.
  Imagine using CC to shut off the CC.
  That will be a big topic on a future radio hour, but I need to search for more facts.
  Submit everything you can find about X10.
  EDITING MY WAY BACK IN
  PAY DIRT!
  YES, wikipedia has it, and the website was right… x10.com
  http://en.wikipedia.org/wiki/X10_Wireless_Technology
April 20, 2012 at 5:54 pm #25783

rock95seven
Total posts : 0
I can say from experience that those intercoms tend to have some great range if they are on the same power lines serving i suppose the same neighborhood.
Once upon a time while doing housework i had to carry somethings into another room that had one of the intercoms (same exact model as MRAM’s) installed and it was on. I heard at first what i thought was someone in trouble but i was the only person home at the time. Who could have been in distress and where were they?
As i crossed the room to where the intercom was on the dresser i quickly realized what i heard was not someone in trouble but rather uh er well a couple in the neighborhood was enjoying each others company and it didn’t take me long to turn off the intercom and leave the room lol .
So the intercoms seem to have some range to them over the power lines. They had to be some distance from our house since the area i was living in at the time had acres of farm land in between homes sometimes as much as 10 acres or more.
April 20, 2012 at 7:25 pm #25784

Carl Blare
Total posts : 0
The story of accidentally overhearing “someone out there” from your own home, reminds me of a story from 20-years ago.
A radio friend introduced me to a professional couple (both in high positions) who felt there was a chance they were being bugged. My particular experience in such things was very limited, but one thing I was able to inform them is that their intercom could possibly be monitored from elsewhere in the neighborhood without their knowledge. According to its manual it was on a low frequency, perhaps 160kHz or so.
I didn’t really understood how it worked, but I knew that “it worked somehow.”
April 21, 2012 at 7:32 pm #25798

MICRO1700
Total posts : 0
Most of you know, but I’ll just give a brief recap.
I have a 6 watt 1971 LPB AM vacuum tube transmitter,
model RC-6A. (It’s a real joy to have this unit.)
The RF output is feeding a 10 dB pad (for isolation)
which then goes to a physically large LC, which is
tuned for max RF or minimum SWR on the transmitter
side. There is an AC extension cord feeding the
transmitter, and it is wrapped around the LC. There
is no direct connection to the A.C. line.
I did some brief experiments, because I have no desire
to break the law regarding Part 15.
There were some intermittent problems with the LC which I
discovered and fixed. That issue seems to explain why
I had some success in the beginning about 2 weeks ago,
and then had no results at all. (By success, I mean driving
under some power lines in my neighborhood and hearing
my signal.)
Although I don’t have a lot of data yet, I can say this:
The set-up works better when it is loosely coupled to
the AC line. One or two wraps of AC cord around the
LC (which is about a foot square) works a lot better
than many turns of AC cord around the LC (heavier coupling.)
With loose coupling, I can hear the signal under the power lines
on adjacent streets relative to my house. Also, when the
AC is loosely coupled, I get a definite RF peak and SWR minimum
(on the transmitter side). That is – the readings are very
obvious and defined under those conditions.
With heavy coupling, such as 8 or 10 turns of extension
cord around the LC, there is no definite RF peak or SWR
minimum as the LC is tuned. Actually, that’s not quite
right – there is a very very broad RF peak, and a very
slight SWR minimum, but they are so broad the reading
variations are almost not noticed. (This does not
surprise me.)
So loose coupling is better.
When I get the commercial coupler (I’m expecting),
that will be great,
but experiments with the homemade system may
continue.
By the way, I read the messages on this forum about
the LF wireless CC intercoms. Man – I wish we had
one to open up and observe how the coupling is done.
Thanks for reading this.
Bruce, DOGGRADIO STUDIO 2
- April 21, 2012 at 8:17 pm #25799
  
  Carl Blare
  Total posts : 0
  This may be good news for Doggradio 2, regarding a post from MRAM giving us a pdf and illustration of a 5-Watt carrier current transmitter from 1973.
  The coupling method is of special interest.
  http://www.part15.us/node/3448
  - April 21, 2012 at 10:43 pm #25800
    
    MICRO1700
    Total posts : 0
    I’m pretty sure I was sitting in my high school
    library in 1973, when somebody handed me
    that article from Popular Electronics.
    I remember being amazed that the 5 watt RF
    energy went back into the power line via a
    couple of .01 uF (?) capacitors. RF chokes were
    put in front of the transmitter power supply
    so the 5 watt RF AM signal would stay out of
    that end of the transmitter. The RF out from
    the final tube went through some kind of
    transformer.
    But the thing was – those caps bridging the
    gap like that. I will never forget seeing that.
    RFB has always said this IS NOT the way to do
    it, HOWEVER, from a historical standpoint this
    schematic is very interesting anyway.
    i also remember that the schematic was put in
    the article, but I never saw a photograph of the
    actual transmitter. It makes me wonder if such
    a unit was ever really built.
    If I had the ability to build that thing THEN,
    it would have been a really cool thing. Provided
    i didn’t blow myself up.
    The University of Connecticut had WHUS FM/91.7 in
    1973, running a little more than 3000 watts.
    But WHUS AM (CARRIER CURRENT on 670 kHz (?))
    was often simulcasting the FM program.
    These guys at WHUS really knew what they were
    doing. They would run the FM/AM simulcast, and when
    a PSA was run on the FM, they would flip a switch
    on the main control board, splitting the program
    briefly – and run an advertisement on the 670 AM
    AT THE SAME TIME.
    So two cart machines were going. The PSA was on
    91.7, and the commercial was on 670 CC. When
    both the different carts were done, they would throw
    the switch BACK, combining the AM and FM again.
    It was impressive, and – it was legal, of course to
    run commercials on the AM 670 CC. And they did
    sell ads for 670 – for a while – I don’t know how
    long that worked out for them.
    It was early in my radio tinkering and listening when
    I realized WHUS, 91.7, at the University of Connecticut
    had a 670 AM CC, and WWUH, 91.3, at the University of
    Hartford, had WWUH AM CC on 640 kHz.
    I didn’t understand what that really meant until a
    few years later.
    I’ll have to go back and take a look at that CC schematic
    again. It does bring back memories.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - April 21, 2012 at 11:05 pm #25801
      
      MICRO1700
      Total posts : 0
      Somewhere on the net, is a 2 watt vacuum tube CC
      schematic that looks similar to the 5 watt circuit
      mentioned above.
      I think a lot of people on this board have seen
      that 2 watt circuit, also.
      The guy who published the Popular Electronics
      5 watt transmitter made no mention of neutral
      injection. I wonder why or why not?
      Actually – I had never heard of neutral injection
      either – UNTIL I came here to PART15.US.
      Thanks again,
      Bruce, DOGGRADIO STUDIO 2
    - April 25, 2012 at 7:02 am #25851
      
      MICRO1700
      Total posts : 0
      Because my CC coupler is homemade, I conduct
      experiments late at night after midnight
      usually.
      This check involves NO DIRECT CONNECTION
      to the AC line. (Just like my coupler.)
      All I did was plug an extension cord
      into the wall socket. Then I got
      a CB/HAM field strength meter – you
      know – the kind that costs 20 or 30 dollars.
      I just wrapped the extension cord around
      the antenna of the field strength meter
      that I was holding in my hand. The other
      end of the extension cord was not connected
      to anything.
      I received a very very small meter reading. It
      was just a little bit more than zero, but
      it was something. I think this field strength
      meter probably uses a diode like a 1N34.
      Knowing that a 1N34 takes about 0.2 or 0.3
      volts to turn on and drive the meter tells
      me that there is some RF voltage on my
      house AC line, just like there is supposed
      to be. (And there was no direct connection.)
      To be sure this was really coming from my
      transmitter, I put a timer on the transmitter
      to turn it off a minute of so.
      And I just stood there – holding the meter,
      with the AC cord wrapped around the antenna.
      I had a radio on, and was listening to
      the signal. I watched the slight deflection
      on the meter. And I watched and I watched.
      A minute or two passed, and I heard the timer
      turn off the transmitter – and the signal
      disappeared from the radio. At the same time,
      the needle on the FS meter fell down to zero!
      This was in the next room about 30 feet away
      from the transmitter.
      Then I went to the other end of the house and
      tried it. The results were very similar. I
      received a very very small reading on the FS
      meter. When the timer turned the transmitter
      off, the small reading dropped to zero.
      So I guess that shows that the coupler is
      putting some RF energy into the AC line.
      For whatever it’s worth.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 25, 2012 at 5:33 pm #25853
      
      Carl Blare
      Total posts : 0
      Still operating daily at a temporary frequency of 670kHz with 2-Watts neutral injection. I have made note that neutral injection in this case is very stable. Every morning and evening I check the SWR and it never varies from 1.5:1.
      Have prepared to order parts to re-build the output filter for the permanent frequency of 970kHz.
      Am also wondering about having a backup transmitter, and the idea of the moment is to rebuild the Ramsey AM25 according to Radio8Z’s instructions, with a linear amplifier to reach 2-Watts at 50-ohms.
      That plan makes maximum use of on-hand resources, as there is no other application for the Ramsey at this time.
      ABOUT Doggradio2’s EXPERIMENT WITH A METER.
      It does appear that you saw enough of the AM CC signal on your meter to indicate its presence on the AC line. Evidently the 60Hz AC energy is below the range of you meter.
      With that small reading you can try to find coupling combinations that boost the RF reading on that meter.
    - April 25, 2012 at 9:29 pm #25856
      
      MICRO1700
      Total posts : 0
      Thanks for your feedback.
      I’m glad your CC system is stable.
      That’s a great idea about using the
      AM-25 as a backup.
      Is that AMP for the AM-25 2 watts input
      or two watts output?
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 26, 2012 at 12:06 am #25863
      
      RFB
      Total posts : 0
      I sent you an email containing both an image and schematic of a 10 watt solid state MW CC amplifier shortly after you won the auction on ebay for your TCU-30 coupler. If you can find that and print out the image and schematic, your all set to build a very stable and clean linear for that AM-25, and there you go, a complete backup system.
      RFB
    - April 26, 2012 at 12:11 am #25865
      
      RFB
      Total posts : 0
      “So I guess that shows that the coupler is
      putting some RF energy into the AC line.”
      Depending on what is on the line, the meter may also indicate the EM field produced on electrical wiring when current flows through them. Heavy loads create even stronger magnetic fields along the length of the wires which could end up being added to the signal your trying to measure.
      Also consider the other induced noises on the lines by inductive loads. This stuff may also give false readings.
      Your going in the right direction Bruce. Just keep in mind that the AC lines do have a bunch of garbage on them and could be picked up by the meter.
      RFB
    - April 26, 2012 at 12:15 am #25866
      
      Carl Blare
      Total posts : 0
      Yes, RFB, the linear amp I had in mind is exactly from the diagram you sent. We are talking serious backup so that 970 will never go dark.
    - April 26, 2012 at 2:42 am #25870
      
      MICRO1700
      Total posts : 0
      Well, RFB – thanks for the info on
      detecting RF on the AC line.
      This testing at night – – I feel like
      a 250 watt daytimer testing during
      the 12:AM to 6:AM test period. (Or
      whatever the time is.)
      It’s REALLY BEWILDERING, but
      really really fun, too!
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 26, 2012 at 5:53 am #25872
      
      MICRO1700
      Total posts : 0
      So it’s about 12:30 AM here in good
      old Connecticut. (About 45 minutes ago.)
      I fired up the experimental CC
      transmitter/coupler set-up to look at
      the near field. 1020 kHz.
      I ventured out of the house and down
      the street.
      The near field disappeared and I kept
      walking. (The near field seems to be
      in compliance with FCC regs. by the way.)
      Then:
      KDKA/1020 in Pennsylvania was not very strong.
      I had heard a bit of what sounded like auroral
      conditions earlier in the night.
      Did we have a spike of solar activity recently?
      What is this hash noise? WTIC has IBOC,
      but they are on 1080. This is a selective
      radio, so what’s going on?
      Oh yeah, that’s right, it’s WBZ in Boston.
      Well, I really like WBZ, so they can do
      whatever they want as far as I am concerned.
      They are on 1030. If they have IBOC noise
      on 1020, well that’s OK with me. I can just
      null it out. (Although, I know of a station
      in New York on 1040 that is very very unhappy
      about the IBOC hash from WBZ, and I think
      that they should be unhappy. If I owned a
      REAL RADIO STATION, and it was getting pounded
      by IBOC hash at night, I’d be pretty miffed.
      Alright, that’s enough of that.
      BUT THEN – WHAT IS THIS?
      “R R” in Morse code, coming RIGHT OVER
      everything on the channel. Yikes!
      Radio Reloj is HERE, TOO?? ON 1020???
      GOOD GRIEF!
      All though a lot of us have heard them
      on 570 kHz, RADIO RELOJ is all over the place.
      I have heard them on 790, 860, and 1010,
      as well. SO NOW, there they are on 1020!
      That’s five frequencies for me, as near
      as I can recall. I actually think I have
      heard them in some other spots on the AM
      dial, but my records are incomplete.
      So I LOOKED THEM UP. Radio Reloj has
      22, yes count them, 22 transmitters in the
      AM band, and 16, count them – 16 transmitters
      in the FM band. A prominent FM DXer in
      Massachusetts heard them on 107.5 during
      his morning commute, a couple of years ago,
      via E-skip. (I wish I was there for THAT ONE.)
      Anywayyyyyy…
      I walked back to the house, turned the
      experimental set-up off, and did some
      chores.
      Now I can’t sleep. But that’s OK.
      That’s why I’m typing this.
      It’s much later now, because I don’t
      type very fast.
      Maybe I’ll do a little more AM BCB
      listening, and call it a day.
      Best Wishes,
      Bruce, DRS2
    - April 26, 2012 at 12:51 pm #25873
      
      Carl Blare
      Total posts : 0
      Doggradio 2 said he was out late after midnight and heard “hash noise.”
      Last night well after midnight I heard loud static popping coming from a radio on the other side of the wall left turned on after 670kHz (my CC station) had turned off. I had been asleep, but I wondered if a thunderstorm was coming, but there were no storms reported in the area. The popping was constant, like popcorn, and it was across the whole dial and on long wave, but not much on shortwave.
      I heard somewhere that radio static has been known to occur when an earthquake was eminent, but we did not have an earthquake and this morning the static is quiet.
      When unable to sleep I have a solution that worked everytime with my wife, when she couldn’t sleep. I said, “I will tell you my life story.” And I started, “It all began on 11th Street in a small town in Wisconsin.” By then she would be sound asleep.
    - April 26, 2012 at 3:10 pm #25875
      
      MICRO1700
      Total posts : 0
      I LOVE IT!
      I’ll be back with more comments in the
      fairly near future.
      Bruce, DRS2
    - April 26, 2012 at 9:52 pm #25878
      
      Ken Norris
      Total posts : 0
      A week or so ago, it could’ve been Old Sol acting up, but not today:
      http://www.swpc.noaa.gov/today.html
    - April 26, 2012 at 10:32 pm #25879
      
      Carl Blare
      Total posts : 0
      If I understand correctly, the solar chart linked by Free Harbor Tiny Radio was from a week ago, but when I linked to it just now it is updated to today’s date and shows a lot of solar racket. I am guessing that the odd noise last night was indeed a message from the sun!
    - April 26, 2012 at 11:09 pm #25880
      
      RFB
      Total posts : 0
      Depending on how large the CME is, and what direction it flings, is what determines the time frame of it hitting the Earth and its duration.
      A CME can occur days before we see the effects. If massive enough, that CME can cause disruptions for hours and even days at a time. All forms of communication and electrical systems will be affected.
      Best way to monitor is to log on to the SOHO site and watch the daily SOHO images and videos of the Sun. Right now there is one that shows a very huge CME discharge. They call it the Pick of the Week. Note the massive CME shooting to the Sun’s North West. That is ONE HUGE CME, which occured on April 20. There have been much larger CME’s recorded by SOHO before which would make this one look like a baby shower.
      Welcome to the real world/universe/cosmos reality show! Where the Sun never lies or holds anything back!
      RFB
April 27, 2012 at 3:57 am #25886

MICRO1700
Total posts : 0
When the sun shoots out a flare, we
see evidence of that in the form of
light traveling at the speed of light.
(Makes sense,)
There is that roughly 8 minute lag
from when the event takes place to
when we detect it with our eyes.
I just can’t remember what kind of
particles hit the earth later, and
what the time lag is for those
particles.
More testing of the great 1020 is
to follow tonight. A small test
will occur in about an hour, where
the coupling between the LC primary
and the secondary will be adjusted.
I have to get some better data on this.
Best Wishes,
Bruce, DRS2
- April 27, 2012 at 4:12 am #25888
  
  Carl Blare
  Total posts : 0
  After reading your post Doggradio 2 I set the dial at 1020 kHz and a very loud, clear, big band theme was playing, followed by Jim Bohannon and his show, probably on KDKA, Pittsburgh, PA. The signal is fading almost totally away, then back in very loud, like rolling crests on the ocean.
  I am hoping on one of the fade outs to hear Hartford, Connecticut.
  - April 27, 2012 at 11:05 am #25895
    
    MICRO1700
    Total posts : 0
    I really enjoy the way you write,
    Carl.
    One paragraph makes the reader feel
    good.
    I hope to have some more real data
    on this coupling issue soon.
    The secondary (AC cord) has been
    wrapped around the primary (LC) with
    different amounts of turns.
    First I started with two turns. That
    worked pretty well – but there are so
    many variables to consider.
    Then I went to
    about 8. That didn’t work at all.
    Then I went to one. Actually one
    secondary turn hasn’t been as good
    as two. However, my data shows that
    tine of day is an issue. Things do
    not seem to work very well when
    people come home at dinner time and
    turn on all of their appliances.
    (But that’s only speculation.)
    I also had to move to an outlet on
    the other end of the room. That’s
    a whole other variable.
    So it’s going to be test test test.
    And write down everything. And the
    tests will be extremely brief.
    Then the whole thing has to be shielded.
    But the shielding will effect everything
    else.
    I am also tinkering with a coil
    for the 1690 Part 15.219 transmitter.
    It will be like the one I had before, with
    many taps. But there will be some kind of
    variable section.
    Thanks again for the cool message.
    Best Wishes,
    Bruce, DRS2
    - April 27, 2012 at 8:58 pm #25903
      
      Carl Blare
      Total posts : 0
      When I first reported that our CC transmitter could be heard on the auto radio for a strong 2.5 blocks before dropping into the noise, RFB suggested walking up to a power pole just beyond the signal drop-off point and holding a portable radio against the ground wire, which he estimated would probably reveal that the signal was till following the neutral path into homes further on down.
      I was reluctant to do that, because of the time my wife and I took a nice walk to the gasoline station to get a can of gasoline for the power mower. As we walked home we were tailed by a police car that hung back about 150-feet, as a neighbor had “reported” us for carrying gasoline on the public sidewalk. I certainly do not want to be reported for “holding a box against the power pole.”
      But today while driving I noticed that there are indeed two poles just beyond the signal drop off point, so I ran the car right alongside each pole and bongo! 670 AM surged up just near the ground wires!
    - April 27, 2012 at 10:32 pm #25904
      
      RFB
      Total posts : 0
      “my wife and I took a nice walk to the gasoline station to get a can of gasoline for the power mower. As we walked home we were tailed by a police car that hung back about 150-feet, as a neighbor had “reported” us for carrying gasoline on the public sidewalk. I certainly do not want to be reported for “holding a box against the power pole.”
      Imagine that. Being reported to police for carrying a gas can from the gas station back home to put into the mower. So watch out everyone…you are a terrorist if you run out of gas and end up walking to the gas station carrying that red gas can with you!! :/
      What’s next…tattle tale on anyone who eats too many beans and alters the carbon footprint offset for the elites?
      Pathetic. So much for home of the brave.
      For the pole test, simply pretend your out for a walk sporting your radio to listen to, and go up to the pole and act as if your resting..leaning against the pole to relax.
      Unless the American flag came down and the Swastika flag went up, there is no law saying ye cannot rest up against utility pole…or carry a gas can filled with gas to put into your empty gas tank..on a car or power mower.
      GET REAL SHEEPLE!!!
      “But today while driving I noticed that there are indeed two poles just beyond the signal drop off point, so I ran the car right alongside each pole and bongo! 670 AM surged up just near the ground wires!”
      Back on topic…now you understand how a CC system works. And your CC system is doing EXACTLY what it is supposed to be doing, keeping that signal on the line and producing enough inductive field (near) for radios plugged into the grid to pick up the signal past the drop off point.
      This is the BIG difference between a 219 setup and 221 setup. There is NO far field beyond that drop off point. It’s all inductive, near field EM propagation. Now for the bigger test, go much further past the drop off point, do the same test and see if that signal is still on the wire 4 blocks away, then 5 blocks, 6 and so on.
      RFB
    - April 28, 2012 at 4:24 am #25907
      
      Carl Blare
      Total posts : 0
      The Carrier Current transmitter is in the basement, way over on the other side. Turning it on and turning it off requires a major days trek to go up and down. In the morning I don’t mind at all, but at night I would rather not bother.
      Somewhere way in the future is a remote control method to turn it off from up here in a convenient location. But I didn’t do that today and I won’t do it tomorrow.
      Last Saturday night 670kHz CC was left ON all night, dead carrier.
      My motivation at the present moment for presenting here is the old saw that “one thing leads to another.” We already know what the “one thing” is, namely, avoidance of turning off the CC transmitter. What would be the “another”? That’s easy. NOT turning it off!
      Solution: stay on the air 24-hours a day. What? Oh, no! I’d hate that. Yet, what a relief it would be not to go down there every night.
      The lesser of two evils. Just like voting in an election.
April 28, 2012 at 5:25 am #25908

MICRO1700
Total posts : 0
I took the coil apart and tightened up
the primary. The I expanded the
secondary from one turn to two, and
coupled it very tightly, tighter than
any windings I did before.
I powered up. Previously, there had
been a HUGE external field off of the
LC coupler. It is now much much weaker.
by a very significant amount. Peaking
the RF was easy. Finding the low
SWR on the transmitter side was not.
I do not have the capability to build
an SWR indicator on the AC line side
as of now. But who knows what the
future holds.
There is no way to measure the results
until tomorrow, when the channel is
quiet.
I am also trying to figure out how
to shield this thing.
That’s a whole other ballgame.
Carl, I think RFB and I (and probably
a bunch of other people who are reading
this) will agree that your system is
working correctly.
I haven’t heard from my friend about that
commercial coupler. But he’s very busy.
I have no problem doing these experiments
until the real coupler comes along. This
is a lot of fun.
Best Wishes,
Bruce, DRS2
- April 28, 2012 at 6:50 am #25909
  
  MICRO1700
  Total posts : 0
  I mentioned before that I had made
  a crude device to detect my transmitter
  RF energy on the AC line. I believe
  it works – in that – it shows there is
  RF present on the line. It does not
  show how the RF got there. So in other
  words, it does not tell you that the
  CC system is operating correctly. It is
  just a very crude indicator.
  It is an AC extension cord terminated
  in a wall wart. The wall wart is just
  a load for the extension cord to feed.
  This cord is then wrapped many many times
  around the whip antenna of an inexpensive
  (cheap) CB/ham field strength meter. It is really
  the CC RF coupler operating in reverse.
  In both cases, there is no direct connection
  to the AC line.
  As mentioned before, this meter probably
  uses something like a 1N34 diode that
  has to get enough RF voltage to turn on.
  (Probably about 0.2 or 0.3 volts.)
  The energy drives the meter, and hopefully,
  causes it to give some kind of indication –
  which is supposed to say, “Hey! There’s
  RF here!”
  Granted, only 500 miliwatts is going into
  the coupler after the 10 dB attenuator,
  which is there to protect the transmitter
  final amp tube. But I had some
  disappointing observations from this meter.
  In my daughter’s room upstairs, and in the
  actual outlet being fed, there is a
  significant reading on the meter (about
  one third scale.) However,
  as RFB indicated before, this could be just
  from RF coupling through the air, because
  nothing is shielded.
  At the other end of the house, and in the
  kitchen, there is a very tiny indication
  on the meter that you can barely see.
  However, it does take 0.2 or 0.3 volts
  to turn on the diode, so some RF is
  there. Again, the RF appearing there might
  be coupled through the air. And not through
  the line at all. I also received a small RF
  reading in the cellar. (In all cases, if the
  transmitter is turned off, these readings
  go away.)
  There was no RF indication whatsoever in our
  bathroom. (We only have one.) The bathroom
  outlet is a GFI, so I’m not sure what that
  means. But if there is no RF in our bathroom,
  how can it be going down the street or
  down the block?
  I’m also wondering how my initial test seemed to
  go so well. We heard the signal very weakly
  around 15 different city blocks the very first
  time I put this thing together. It was our
  very first trip out in the car. Perhaps
  a connection is broken that I can not find
  or see.
  I’m not complaining. This is a lot of fun.
  But I can see that a simple home made CC
  coupler is not necessarily a viable project.
  However, I’ll still get my wife to drive me
  around in the morning. Perhaps we will get
  some interesting results.
  And I’m sure I’ll keep tinkering with this thing.
  Probably for a long time. I wish we all knew
  how those CC 160 kHz FM intercoms work.
  Best Wishes,
  Bruce, DOGRADIO STUDIO 2
  - April 28, 2012 at 9:47 pm #25918
    
    RFB
    Total posts : 0
    Those just coupled up to the power through capacitors, usually .01uf 3kv ceramics. The ones I have torn apart never had any real matching network to speak of. But there were various makes and coupling approaches.
    The earlier results Bruce were indeed from free radiating RF coming off the homemade coupler. Probably a combination of both CC and direct radiation.
    Once the homemade coupler is shielded, the task of perfecting the coupler itself will become much easier as the majority of the signal will have but one way to escape..via the secondary winding of the coupler core.
    RFB
    - April 29, 2012 at 6:18 am #25924
      
      MICRO1700
      Total posts : 0
      Hi RFB, thanks for popping in. I
      completely agree with everything
      you say, but I have a few questions.
      I do not have the eyesight to
      build big structures out of metal.
      And that LC section is pretty big.
      The best I can do right now is
      probably a big cardboard box wrapped
      in lots of aluminum foil. I still
      see this as a “science fair” experiment
      anyway. And a temporary one.
      Then I thought:
      Get a good high voltage .01uf cap,
      put a low amperage fuse on it, and
      then hook it into the hottest RF
      section of the LC. (The transmitter
      is isolated by the attenuator, so I
      don’t think it’s final RF stage will
      have a problem.) Then take the fused
      end, and hook it to the neutral wire
      of an AC cord. And plug it into the
      the AC outlet. (Actually, I would
      do this LAST.) Then take the RF ground
      from the transmitter, take another good
      .01uf cap, and a fuse, put them in the
      line, and ground it to an earth ground.
      (Maybe you don’t need the .01uf and the
      fuse in the ground line – but you
      would know. You’re the real RF
      engineer, and I’m just an uneducated
      dude.) Would this put more energy into
      the AC power line? (Who knows?)
      Then I thought, do you need the LC at all?
      The transmitter RF final is isolated by
      the 10 db attenuator. There might be
      more transfer of actual power without
      the LC, and the shielding job will be
      so much easier because the enclosure
      can just be a small metal box.
      Those of you out there who are reading
      this that we do not know – don’t try this
      idea mentioned above.
      I don’t know if it’s a good idea yet.
      It might be good, might be OK, might be
      horrible.
      RFB, my friend, do you have any comments
      on this?
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 29, 2012 at 5:25 pm #25933
      
      RFB
      Total posts : 0
      Well the problem I see with coupling in that manner is the lack of proper isolation as well as proper matching. Remember that the attenuator is providing your TX with a constant load of 50 ohms, attenuating the RF power level, but does it convert down to the much lower impedance of the grid?
      When inductance changes happen on the line, these inductive changes will be seen by the TX due to lack of isolation from input to output. Your air coupler coil has a better isolation factor than what would be given by a simple capacitor/fuse connection directly to the lines/neutral.
      It’s worth experimenting with that approach to see the effects of the line changes vs loading and coupling. It would make a very good learning tool!
      RFB
    - April 29, 2012 at 6:22 pm #25936
      
      MICRO1700
      Total posts : 0
      I think you said the impedance of the AC
      line is something like 0.2 ohms?
      For an experiment, if I put a jumper
      directly across the output of my attenuator,
      and the SWR on the transmit side is still
      good, then the transmitter is safe. However,
      that does not answer the problem about
      power transfer, that’s a whole different
      animal of course. (And I would be removing
      that jumper first before I did anything else.)
      OK. I’m going to proceed with the cap/fuse
      experiment very slowly. Very slowly. This
      house was built in 1931, and I am willing to
      bet that some of the AC outlets might be
      wired backwards. But I have a tester to
      check that.
      Thanks RFB. This will be fun, too, which
      for me is what it’s all about.
      Best Wishes,
      Bruce, DOGGRADIO STUDIO 2
    - April 29, 2012 at 8:02 pm #25940
      
      RFB
      Total posts : 0
      In most cases the line impedance off the grid (post step-down transformer winding) is usually 2 ohms or so, sometimes a little higher. This impedance is also dependent upon how many homes are tied to that secondary of the step down transformer and loads on each utility drop. I have seen the impedance on some grids lower than 1 ohm, but in most neighborhood situations that impedance is anywhere between 5 and 2 ohms.
      Once in a while you get the very strange impedance like Carl encountered. His “hot” sides were showing up as high as 18 ohms! What was even more strange is the coupler was not able to tune out the excess capacitance thus the high vswr. It was not until he coupled to the neutral and ran an isolated ground rod for the return could he tune the system to hit a 1:5:1 vswr.
      Remember Bruce, that the coupling methods in the hey day used LC type circuits and tubes for the finals which were far more capable of handling mis-matches than solid state units. There was more room for error in those setups and far less inductive loading on the grids than today.
      If after installing the shunt resistor on the output of the attenuator shows the transmitter to still see a consistent load and does not change when removing the shunt resistor or installing it, then the TX will be fine and the attenuator is indeed maintaining the proper impedance to the TX no matter what the output does..next to a direct dead short. This is important to keep a constant load to the TX which in turn helps maximize the coupling efficiency to the grid no matter what changes take place on that grid.
      Let us know how it goes!
      RFB
April 29, 2012 at 9:09 pm #25942

MICRO1700
Total posts : 0
This will be a fun experiment.
I will try some resistors in the 2 to
5 ohm range across the attenuator.
Then I will remove the test resistor
and go to the next step if the transmitter
SWR results look good.
And that will be going from the
attenuator right
to the cap/fuse/neutral. For this
experiment, I will not use the LC,
because I just want to observe the
external RF radiation, or lack thereof,
hopefully.
I have to put this together slowly. I
want to get some real good caps for
this, too. Radio Shack may or may not
have the caps I need. I may have to
go somewhere else.
Thanks again, and stand by.
Best Wishes,
Bruce, DOGRADIO STUDIO 2
- April 30, 2012 at 1:50 am #25951
  
  Carl Blare
  Total posts : 0
  I have two stories from recent experience, and one of them has to do with carrier current.
  But first I must say I am following Doggradio2’s CC experiments with great interest. Now that I have CC in my life I will never be without it.
  I’ve described the complaint I have that I must trek down into the far reaches of the basement to shut off 670kHz at the end of the broadcast day, and have already left the carrier on all night which violates my own station policy.
  This weekend I went on strike regarding the basement and solved the problem by scheduling programming for 24-hours a day for the whole weekend.
  The second story from experience will appear in the AMT5000 Review column.
  - April 30, 2012 at 6:04 am #25955
    
    MICRO1700
    Total posts : 0
    I have comments for both of you.
    First for RFB, a couple of minor
    questions. For the .01 uf cap or
    caps I need – Radio Shack only has
    1 KV disc ceramic types. These cost
    about a buck. I was hoping they
    would have something made of better
    material. I’m making the assumption
    that these would be OK for temporary
    experimentation, but that something
    better would be needed for permanent
    use. Also, I’ve been looking at fuses.
    Do you have any kind that you would
    recommend?
    And for you Carl, I’m very glad your
    CC set-up is working so well. I
    wish we could figure out some way
    to turn on and off your transmitter by
    remote control. The LF carrier current
    remote controls, or even the radio
    controlled remotes would be over loaded
    by all of that RF. I know, because
    I have both kinds. Either can be used
    to turn lamps or appliances on or off,
    but they sure don’t work when there is
    a lot of RF floating around. For instance,
    I can use the radio controlled remote to
    turn on my CC transmitter, but then I
    cannot turn the transmitter off. The
    simple receiver is overloaded at that
    point, and cannot receive the command
    to go off signal.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - April 30, 2012 at 9:14 pm #25965
      
      RFB
      Total posts : 0
      For Carl’s control issue, that can be solved by adding a remote power switch using low voltage DC controlling a small SPDT relay across the power switch inside the TX. Add a power on indicator (tap the red LED) and wala.
      The capacitor voltage rating of 1Kv will suffice for experimenting purposes, but make sure you add a fast blow fuse no higher than 1 amp. You might also want to add a 100uH choke, perhaps two or more, in series with your capacitor/fuse direct coupling circuit so as to add some inductance to the path which will help “tune” down to the lower impedance for better results.
      RFB
April 30, 2012 at 10:07 pm #25969

MICRO1700
Total posts : 0
Some fuses are rated at 250 volts.
Say the fuse is rated at one amp/250 V and
the voltage in actual use is 120.
If more than one amp goes through the
fuse at the lower voltage (120 vs 250)
will the fuse blow?
I never stopped to think about this –
is the fuse’s actual point where it
blows based on JUST CURRENT?
Or is it the VOLTS x AMPS that determines
when the fuse will blow? Or perhaps there
is a characteristic curve that applies?
Then my mind asked – maybe different
kinds of fuses blow under different
conditions. (I’m not talking about thermal
fuses, though – they are a different animal,
I guess.)
Thanks for the additional info on the RF chokes,
Yup, that sure does make sense to me.
Bruce,DRS2
- April 30, 2012 at 11:49 pm #25973
  
  RFB
  Total posts : 0
  You have two things working in your favor. The low level RF being applied and the isolation capacitor/fuse connection. No current is being drawn from the source. The RF voltage applied from the attenuator is well below the 250v rating of the fuse.
  600mW is .6VA. The 1 amp rating is a very good choice with adequate head room but not so much the protection is out of reach if there was a problem..such as the 1Kv cap shorting.
  RFB
  - April 30, 2012 at 11:55 pm #25975
    
    MICRO1700
    Total posts : 0
    I’ve learned more from Part 15 radio in a few years –
    than 40 years of ham radio!
    Thanks again!
    Bruce, DRS2
    - May 1, 2012 at 1:00 am #25976
      
      mram1500
      Total posts : 0
      The voltage rating on the fuse is for the flash over rating of the fuse enclosure. If it’s rated 1 amp, it doesn’t matter what the voltage is up to the rated voltage. The fuse will open when you exceed that current.
      So, if you buy a fuse rated 1 amp 12 volt you would not want to use that if the open circuit voltage exceeded 12 volts. In your case you should be OK up to 250 volts.
      We bought bulk amounts of inline fuses for vehicle use. They look identical to the higher rated voltage fuses but only carry a 24 volt rating. Not a good choice for AC line applications.
May 1, 2012 at 4:18 am #25990

Ken Norris
Total posts : 0
Hmmm … I wonder if that might work … to get the injected signal to go further.
The TH I’m using right now seems a lot more stable than I would have expected for what it is. Even at very close proximity, it doesn’t seem to splatter into adjacent frequencies very much. Maybe I just got a ‘good -un’. So adding power with a good clean RF amp should work ….
What say?
- May 1, 2012 at 10:01 am #25992
  
  RFB
  Total posts : 0
  Well the TH external ATU output has no low pass filtering so any linear used would need to have a very good low pass filter like that found in LPB’s transmitters.
  The TH will drive an LPB linear just fine. 🙂
  If intending to drive an LPB linear, and depending on intended operating frequency, the filter may need to be changed for the particular section of the MW band where your frequency will be.
  Low 530-830
  Mid 830-1270
  Hi 1270-1710
  RFB
  - May 1, 2012 at 10:39 am #25993
    
    MICRO1700
    Total posts : 0
    MRAM, thank you for the
    additional explanation on
    fuses. This is real good
    info to have. I don’t want
    to blast the transmitter
    into orbital space!
    And Ken, good luck with
    what you are trying to do.
    You’re a better man than
    I am!
    Best Wishes,
    Bruce, DRS2
May 2, 2012 at 2:58 pm #26001

Ultanium
Total posts : 0
Glad to hear you got CC up & running Carl, I have been busy as hell, but am following your progress! RFB, give me a call.
Tommy j
The Cat 87.9fm
May 2, 2012 at 11:17 pm #26006

MICRO1700
Total posts : 0
Hi! It looks like I have
almost all the parts you guys
mentioned to couple directly
into the AC line with the CC set-up.
My only problem is the cap.
I was only able to get a 2 pack of
.01 uf caps – the problem is they
are rated at only 500WVDC max.
I also happen to have a metal-film
.01 uf cap – but it’s voltage rating
is lower – it’s 400 WVDC.
No problem with the 100 uH chokes and
I have a 1 amp 250 volt fast acting fuse.
My question is about the caps. Can I use one
.01 uf 500 volt disk briefly
for a few minutes to see if
the CC system works, or is that a really
bad idea?
How do caps fail – do they short? (I bet
the answer is yes.)
That wouldn’t be so good.
If I put a couple of caps that were
1/2 the value in parallel?? Would that
solve the voltage problem? (2 .005 ufs
in parallel?)
My lack of knowledge is showing here.
Thanks and best wishes,
Bruce, DRS2
P.S. I placed a jumper across the output
of the 10 dB attenuator, and the SWR hardly
went up at all, so I guess that part of the
system is working OK.
- May 3, 2012 at 11:52 pm #26013
  
  Carl Blare
  Total posts : 0
  I used “Start Page” to search for the term “Carrier Current” and have enough links from now until Christmas.
  I decided to come up for air and share a few things I’ve found.
  Bruce, a college CC station recommends 1uF 1kV caps for coupling to the power line.
  I didn’t know that CC can be used for covert surveillance, but it can; little devices can be hidden in sockets, power strips and appliances which send audio AND VIDEO by CC!
  There are instructions for detecting CC signals on the power line.
  My idea is to put a wide-band jamming transmitter on CC and take a nap.
  As I sort through this stuff I will link some of it, if it hasn’t already been linked in the past.
  - May 4, 2012 at 2:36 am #26014
    
    MICRO1700
    Total posts : 0
    ECHO ECHo ECho Echo echo
    Yup, after asking that last
    question – I have decided to
    wait on this “direct to AC Line”
    circuit, regarding the isolation
    cap.
    Radio Shack does not have one that
    is a high enough voltage and I
    don’t want to mess around with
    this thing.
    There is a really cool electronics
    store that will have a nice big
    jumbo conservatively rated cap.
    I’ll just have to arrange to get
    a ride over there as soon as I can.
    It’s pretty far away, but it will
    be worth the wait.
    Thanks again Carl and everybody for
    all of the advice.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - May 4, 2012 at 1:29 pm #26015
      
      Carl Blare
      Total posts : 0
      The daily carrier current operation from here has been operating at the temporary frequency of 670kHz for several weeks at a power of 2-Watts.
      Now having explored the radiation from the power lines using both the car and a portable, it seems like the signal is reaching less than 100-feet away from the power lines.
      As is often mentioned, the rule of thumb for safe compliance is 200-feet, so today I inched the power up to 2.5-Watts, and we’ll do more surveying to see what has changed out in the field.
    - May 4, 2012 at 2:43 pm #26016
      
      MICRO1700
      Total posts : 0
      Hi Carl!
      It will be interesting to see what
      the results will be from the
      increased power.
      I think what you are doing is great.
      Bruce, DOGGRADIO STUDIO 2
    - May 4, 2012 at 4:28 pm #26017
      
      Carl Blare
      Total posts : 0
      Thanks for following the progress, Bruce, as we are with your experiments in CC.
      Since my last posting, only an hour ago, a violent storm started to happen, so I went through the shutdown drill, all transmitters and computer off, antennas disconnected, and radio silence being maintained.
      That spoiled the fun for the storm and it turned off.
      So all the re-connections were made and we returned to the air and stream, only to hear the storm coming back.
May 4, 2012 at 5:31 pm #26018

MICRO1700
Total posts : 0
I sort of worry about the
weather you have out there.
The obnoxious weather hasn’t
started for us, yet.
There is one thing I like about
it though – although technically
there is no direct correlation,
crummy weather in the spring and
summer is usually followed by
e-skip.
I always get a kick out of E
openings.
I think it is amazing when a semi-local
station gets covered up by a
station that is 1200 miles away,
for an hour or so.
I do not have the time to FM DX like
I used to, be it still is fun
once in a while.
I’m sorry that you have to deal with
that variable weather.
It’s also good you didn’t get blasted
this time.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- May 4, 2012 at 7:07 pm #26019
  
  Carl Blare
  Total posts : 0
  The severe weather here in the middle of the continent seems to skip around, even in close areas…..
  The last time this exact neighborhood was impacted very severely was about 1955 when a funnel ripped right around here and took out the tower of channel 2, which was at the southwest corner of Forest Park. The mangled wreckage was strewn over some apartment houses and parking lots.
  The very base of the tower was preserved, it may still be there, as a mounting spot for microwave to the new tower down by the Mississippi in south city.
  This particular building has been here since the 1920s, so that funnel must have skimmed by.
  Since then the tornadoes have hit x number of miles southwest of here, north of here, northwest of here and a lot of other skips.
  - May 4, 2012 at 9:52 pm #26022
    
    Carl Blare
    Total posts : 0
    My verbal skills are an exaggeration. By that I mean, I may not possess verbal skills of a normal kind. That prefix “ex” always makes me think something is past-tense. For example, an “exaggeration” is a former aggeration; an “example” is a past ample; “excitement is a previous citement; my “explanation”, well, you get the idea.
    Anyway, I am presently “cited” about the fact that the MICA RF capacitors have officially been ordered from Mouser to convert the carrier current transmitter to mid-band, at 970kHz, a good open frequency where I will spend all retirement.
    That’s strange, “retirement” has a different prefix: “re.” Like doing something a second time. First I was tired, then I retired.
May 5, 2012 at 10:45 am #26023

MICRO1700
Total posts : 0
Carl, your last message is a hard act to
follow. I hope you don’t have any trouble
with weather over your way. Keep us posted.
OK. Here’s my question.
I have a partial understanding of how
to phase out hum on a CC signal.
One friend told me you can take some
AC from a low voltage power transformer,
and put some attenuators on it. When
you get the potential down to about
100 mV with the attenuators – then you can
inject it into your audio line. Somehow,
then the hum will cancel itself out. I suppose
you may have to adjust the level of the
hum you are injecting. I also understand
it is best to try to phase out the 120 Hz
component, and not the 60 Hz. But I don’t
understand how the “phasing out” part fits
in. Something seems to be missing here.
This was a quick conversation just in passing.
Do any of you guys have any comments on this?
I have read about this before. If it was on
Part15.US and I’m rehashing it, I apologize.
I just can’t seem to find any more info about
it.
Bruce, DOGGRADIO STUDIO 2
- May 5, 2012 at 1:16 pm #26025
  
  Carl Blare
  Total posts : 0
  Bruce, you have used many of the correct words to discuss the process of eliminating the AC 60 Hz hum and of course 120 Hz hum, etc., but this is one of electronics thorny tricks.
  It is thorny because it is simple, but hard to put into words.
  My explanation won’t help, I hope someone can present it in a better way, a picture could be good….
  A toroid transformer or other “matching” type transformer with identical but opposite windings causes the AC side to “phase-out”, which also means “cancel,” so it cannot back-flow into the audio….
  The same method is used in a telephone to separate the incoming signal from the sending signal…
  To get more esoteric the same method is used to convert left channel and right channel stereo into L+R / L-R for FM stereo transmission.
  Let me look around for a diagram that might help…..
  - May 5, 2012 at 4:33 pm #26026
    
    Carl Blare
    Total posts : 0
    Carrier Current (CC) broadcasting under part 15 deserves equal interest to that of radiant-antenna operation, because of how neatly they complement each other.
    Using the baby monitors and home intercoms as an example, part 15 AM transmitters could be easily manufactured for general home use.
    Or, a simple add-on to the available part 15 transmitters could be offered, making the equipment interchangeable.
    For several days I’ve been rummaging through CC links located by a Start Page search, and although a few of them are worth visiting, many are dead links. Despite it’s great history spanning decades the CC subject is weakly represented on the web.
    Especially lacking are circuit data showing how to build couplers.
    The method I discussed earlier of using phase-cancelation to eliminate 60 Hz hum is apparently hampered by the fact that electric loads cause the hum to increase and decrease as electric appliances are switched on and off, making the phase-matching very difficult to maintain.
    I spent an hour this morning sketching a simplified version of the LPB TCU-30 and realize it does not use the phase-canceling technique, but rather has an elaborate set of transformer/capacitor matching/filtering as a way of tuning for maximum result.
    RFB has mentioned operating both CC and radiated signals at the same time, and indeed, using a method described in a manual within the part15.us library, it would indeed be possible to broadcast on the power lines and antenna using the same frequency.
    Doing this might pose the problem that the CC field readings would appear to be higher than allowed because of the influence of the radiated version of the signal coming from a 3-meter antenna. In such a situation two parts of the rules would literally collide.
    - May 5, 2012 at 10:34 pm #26028
      
      MICRO1700
      Total posts : 0
      Well, the problem with my experimental
      coupling CC set-up was that it was
      going into the power line – but it also
      was radiating. I haven’t given up on
      that experiment, but it will be set aside
      for the time being. What is nice about
      that approach is that – there is no
      direct connection to the AC line. I don’t
      believe the RF radiation was violating FCC
      regs, but then again, the thing wasn’t
      working as it was intended to, either.
      This next try WILL be a direct connection
      into the AC line. RFB said it would be a
      good learning tool, and I’m sure it will be.
      This will be coming soon. By the way, I
      love listening to the LPB RC-6A transmitter.
      I have been running it into the attenuator
      and a small antenna. Just enough to cover
      the house.
      I does sound very good.
      This is sort of what you mention – a simple
      “add on” to get the transmitter to do
      carrier current. Will, it work well?
      Who knows? I enjoy the experimenting regardless.
      So I will report what happens.
      Bruce, DRS2
    - May 5, 2012 at 10:36 pm #26029
      
      MICRO1700
      Total posts : 0
      It’s just a prototype.
      The first test will be tonight.
      Bruce, DRS2
    - May 5, 2012 at 11:18 pm #26030
      
      Carl Blare
      Total posts : 0
      Dear Doggradio Studio 2
      As you test your next carrier current experiment I invite all part 15 members everywhere to toast your launch and wish you the very best.
    - May 6, 2012 at 11:57 am #26033
      
      MICRO1700
      Total posts : 0
      I don’t think this coupler is
      working either.
      However, I tested it at night
      when KDKA/1020 was bombing in.
      We are almost out of the “critical
      hours” time block here in Connecticut.
      I’m going to take a radio out and
      go around the block.
      I’ll Be Back!
      Bruce, DRS2
    - May 6, 2012 at 1:00 pm #26034
      
      MICRO1700
      Total posts : 0
      Well it seems as if this direct
      coupler is working to some degree.
      There is the near field, which
      tapers off at a reasonable distance –
      I believe – to satisfy the FCC regs.
      I walked up my street about 1000 feet.
      The signal was weak under the power
      lines. But in two places where I
      held the receiver up to ground wires
      on telephone poles, the signal came
      in with greater strength. This did
      not happen with the previous external
      coupler – instead, I just received more
      noise. (The power lines are noisy
      around here, which doesn’t help.)
      So this new result with
      this second coupler design shows a
      small but significant change for the better.
      This coupler is just a prototype, but
      I think we might be getting somewhere.
      I do not have a good ground and the
      power into the line is only 1/2 a watt.
      One step at a time. If this experiment
      gives me further proof that it is
      working as it should, I will go see
      my neighborhood friends in their home
      about 8 houses down the street. I will
      have no problem getting in there with
      a radio. But I want further proof first
      that this is working right – and the
      prototype might have to be tweaked. This all
      will take time.
      Bruce, DRS2
    - May 6, 2012 at 1:36 pm #26035
      
      MICRO1700
      Total posts : 0
      I decided to put a jumper around
      the attenuator and run the full
      5 watts into the line.
      I did this for about 5 seconds.
      The SWR reading only went up a
      little bit. In the short time
      it was running, everything seemed to be OK.
      (However, I know there are many
      many variables.) The transmitter
      seemed to be fine. It was happy with
      the low SWR.
      The 100 uH RFCs in the coupler are only
      rated at 2 watts, hence the five second test.
      Under the higher wattage, I don’t know if
      they would just saturate or be destroyed.
      The ratings for the RFCs are specified for
      I kHz, in the audio range. I’m not sure
      what this means. Also, there are two in
      series. I’m not sure what that means, either.
      However, in this “high power” 5 watt test that
      lasted only 5 seconds, the SWR was very very low,
      only slightly higher than it was with the
      attenuator in line.
      I realize the low SWR might mean nothing, because
      there are so many variables.
      Still, it was interesting.
      Bruce, DOGGRADIO STUDIO 2
May 6, 2012 at 5:05 pm #26036

MICRO1700
Total posts : 0
In trying that 5 second 5 watts into
the AC line CC test, I may have
put the jumper over the wrong place
in the attenuation network. Meaning
I still had full or partial attenuation –
instead of none at all – which is what
I wanted.
I just can’t believe that low SWR could
be true. It’s too easy. I must have made
a mistake with the jumper.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
- May 6, 2012 at 6:25 pm #26039
  
  MICRO1700
  Total posts : 0
  Where’s RFB?
  Didn’t I say that already?
  Bruce, DRS2
  - May 7, 2012 at 3:16 am #26043
    
    MICRO1700
    Total posts : 0
    My CC coupler that is going directly
    into the AC line fooled me.
    I thought I had a low SWR, and that
    there was a good power transfer.
    I couldn’t have been more incorrect.
    I had decided to briefly put a 5 watt
    signal into the line. I previously had a
    low SWR reading
    because part of the 10 dB attenuator
    was connected, and I didn’t realize it.
    When I took the attenuator completely out,
    and tried 5 watts again, I read as much reflected
    power as forward power.
    An infinite SWR.
    The more that I learn the more I realize
    what I don’t know.
    That’s OK.
    Back to the drawing board!
    Bruce, DRS2
    - May 7, 2012 at 3:43 am #26044
      
      MICRO1700
      Total posts : 0
      BACK TO THE LC!
      BRUCE, DRS2
    - May 7, 2012 at 7:16 am #26052
      
      RFB
      Total posts : 0
      The problem is the lack of proper TX termination doing the “direct” coupling method while bypassing the matching and attenuator network.
      In order to get the proper match with the “direct” coupler method, there has to be a way for the direct coupler to do 4 things, 1-match the TX, 2-Isolate the TX, 3-Tune to the line, 4-tune out excess capacitance in the line.
      So far, you have three constructed parts to building a whole.
      Keep going! 🙂
      RFB
May 7, 2012 at 7:01 pm #26053

MICRO1700
Total posts : 0
Glad to hear from you. I wondered
where you went. You must have been
busy.
Yup! I’ll keep messing with it.
I have to say, it is A LOT of fun,
and I’m learning a lot.
Everything will be fine as long as
the transmitter doesn’t blow up
into orbital space, and actually,
I’m not gonna let that happen.
Best Wishes,
Bruce, DRS2
- May 8, 2012 at 4:13 am #26060
  
  RFB
  Total posts : 0
  “Glad to hear from you. I wondered where you went. You must have been busy.”
  Indeed. Going from one tower site to another (post winter season maintenance), especially when the distance between sites is as much as 300 miles, well that does tend to keep one out of reach for a bit! No such thing as freebie wi-fi hotspots out in the middle of nowhere! 😉
  Right now I am sitting in a small hotel room using another engineer’s laptop to check in.
  Yep, this home brew coupler is going along fine. Your learning quite a lot with it and finding out already what works and what won’t work. But the neat thing is that you are so close to having a complete coupling system, one that provides both proper TX matching and isolation and also provides a means of variable coupling to the line side. This will be necessary as the line side will change it’s inductive loading effects on the coupler output side as loads change throughout the day and night.
  What you need in between the LC section and the output is a means to measure VSWR on the line side. A VSWR circuit will go between the coupler output and the capacitor/inductor/fuse set. From there it connects to the line..be it neutral or one of the hots. If you want to couple to both hots, simply build a second capacitor/inductor/fuse set for the other hot line.
  I have a complete manual for the TCU-30 coupler, once I get my scanner working I will make a PDF of it and provide that to the Part 15 forum library resources. Once you see the schematic of that commercial coupler, you will be quite surprised at how close your own home made coupler is to one such as a TCU-30.
  Again, all that is missing is a means to measure the VSWR on the line side. Through a wafer switch, you could also make that VSWR circuit measure the TX side and make the VSWR circuit a dual function system. It could help you tune to the line side, as well as monitor and ensure the constant 50 ohm load to the transmitter.
  Please Please Please be careful with this direct coupling approach, particularly working with the hots, and even with the neutral. Safety first and foremost!!
  That advice goes to anyone thinking about working with Carrier Current and the electrical systems. It’s so easy to overlook something by mistake. Sometimes the excitement and rush to fire it up can bite you back with one heck of a zap!
  RFB
May 8, 2012 at 9:34 am #26062

MICRO1700
Total posts : 0
First, I can’t thank you enough
for the information.
And I am being very very careful.
There are several more things I
want to try.
After all of this excitement trying to
make this thing operate, something
struck me.
I AM AFRAID this might be a major question
and/or problem. (With no real answer.)
A while back, the power meter on the side of
our house was removed (by the local utility)
and was replaced by another kind of energy
measuring system.
There is now a unit in our basement that measures
our electrical power expenditure over the required
time, and then apparently transmits this data out
of the house by RF.
The story I have on this is, that somebody drives
by in a local utility truck with a compatible
receiver and their device tells them how much
the power bill will be.
So I’m sure you know what I’m thinking.
And there is no real way to know – will the
CC operation interfere with the utility
wireless “power meter?”
I’m almost laughing now. What if I get this
CC thing running and then a month later I
get a power bill for three hundred billion
gozillion dollars? I don’t have three
hundred billion gozillion dollars. That
would be a problem.
I’m sure there is really no answer to this
question. Every house would be different.
So, if you want to ponder that, and get back
to me, that would be OK. But don’t sweat it,
because there may not be an answer to this
question.
In the meantime, as you’re servicing all of this
stuff in this wide area, be safe and
(I’m not a religious man, but) Godspeed RFB!
Bruce, DOGGRADIO STUDIO 2
- May 8, 2012 at 6:45 pm #26065
  
  Carl Blare
  Total posts : 0
  Godspeed is faster than radar so not to worry.
  Good question about carrier current messing with electric billing methods.
  Maybe it will register as “No Electric Usage.”
  - May 8, 2012 at 7:16 pm #26067
    
    MICRO1700
    Total posts : 0
    Yeah, RFB is servicing radio
    stations – as you know.
    All that driving and unexpected
    stuff that you could find when
    you go into a station. I’ve heard
    a lot of stories from my friends
    in the business. Imagine finding
    a major problem after driving 300
    miles…
    Wouldn’t that be great if “CC/utility
    measuring thing” had the result that you
    mentioned. Carl Blare humor. I wish
    you could bottle it and sell it.
    Everywhere.
    Best Wishes,
    Bruce, DOGGRADIO STUDIO 2
    - May 8, 2012 at 7:52 pm #26069
      
      mram1500
      Total posts : 0
      Our city switched to Automatic Meter Reading a couple years ago. Not all but most meters have been replaced.
      The electric and water meters have data transmitters which are received by neighborhood collection receivers, about 30 citywide. These collectors retransmit the data to central collecting receivers, 3 at key points. From there the data is transfered over fiber to the city Utility Billing office.
      The system uses frequencies in the gigahertz range. So far there’s been no noticable interference to or from the meter system. Most likely your system uses similar frequencies so interference shouldn’t be a problem.
    - May 8, 2012 at 8:26 pm #26071
      
      Carl Blare
      Total posts : 0
      670kHz CC is on its last days while we watch for UPS with the parts for the permanent move to 970kHz. We are running 2.5Watts and the signal radiates out to about 200-ft from the powerline, close to the 238-ft limit stated by RFB (by memory).
      We have found that neutral injection maintains very stable settings, the SWR never needs to be re-adjusted. Readings are taken in the morning and evening.
      Most of the time the SWR is 1:1.5, although once following a heavy rain it went to 1:1.75, but could not be adjusted any lower.
      RFB forecast that with hot-side coupler connection the SWR needs to be re-adjusted several times a day and requires silent carrier, which can be a real chore for a station that feeds several transmitters and a stream, but with neutral injection that is not an issue/
    - May 9, 2012 at 12:45 am #26076
      
      MICRO1700
      Total posts : 0
      Thank you MRAM, that is a comfort to me.
      And Carl, your CC is doing great! It’s a
      major accomplishment.
      I’ll be back.
      Bruce, DRS2
    - May 12, 2012 at 9:24 pm #26170
      
      Carl Blare
      Total posts : 0
      Last Tuesday the temporary CC operation, 2.5Watt on 670kHz, shut down while we prepare to convert the transmitter for its permanent home at 970kHz. But life without CC is like trying to get by after the favorite dog runs away. I re-installed it for a Second Temporary Life.
      This time we are doing 1Watt at 570kHz, with only one guard band on either side. The SWR is 1.75:1
      Now life is wholesome again and I don’t need to go to church; this IS church with towers, antennas, glowing lights and mysterious signals in the night.
    - May 12, 2012 at 9:49 pm #26174
      
      RFB
      Total posts : 0
      You really need to find yourself a decent FIM or something to measure with. At 570 on 1 watt your lucky if that signal is reaching the previous drop off point simply because the lower frequencies require a lot of juice to shove down the line.
      Radio receivers with S meters don’t tell you the real story, nor does driving around. Start hunting for a used IFR or other, hook it up and you will see what I mean.
      RFB
    - May 12, 2012 at 11:06 pm #26176
      
      Carl Blare
      Total posts : 0
      Because I am in this thing for real and love the combined thrill of air radiation and powerline transmission, I accept and appreciate your advice to begin assembling the test array needed to know and control what is actually happening.
      Part of the pleasure of low power life is the building of the system and the improvement of the component parts.
      Perhaps tonight after dark I shall boost the power to 2Watts at 570kHz just for the night.
      Today the “testing” is being done by checking several house radios to make sure that the neighbor frequencies are not being interfered with.
      Too lazy to drive anywhere, too shy to walk around with a portable.
      EXCEPT THAT THIS IDEA JUST POPPED UP FOR FUTURE FIELD BEHAVIOR:
      The way to “blend in” and appear to be official and not suspicious is to wear a yellow orange safety vest with a white hard-hat and get out in the street with meters. Maybe even some orange safety-cones.
    - May 13, 2012 at 4:02 am #26183
      
      RFB
      Total posts : 0
      Using the various radios as a general guide to ensure neighborly manners to co-channel located stations is great on your part. If you do intend to use a radio receiver with an S meter or modify one to have an S meter, when you have the CC system verified have the tech give you their field strength reading at the 157k/f point and note your radio’s S meter position as well as the radio’s physical position etc.
      Then care for that radio like you would that transmitter because that radio will be your referencing base as to what the system is doing.
      Just like the steady patience you had to obtain CC gear, the opportunity to obtain a decent FS or coms analyzer will come around too!
      RFB
    - May 13, 2012 at 10:17 pm #26194
      
      Carl Blare
      Total posts : 0
      Overnight the 570kHz temporary transmission went out as planned with 2Watts, then at daylight the power went back to 1Watt. Keeping the flame low to avoid messing with nearby stations.
      Something interesting, while studying the rules, noticed 15.113 Power Line Carrier Systems. This section describes the technology for power companies to use carrier current for controlling their own system, and specifies the range from 9kHz to 490kHz, using “the minimum power possible to achieve the objective.”
      Of note is that 15.113 is in the section “Unintentional Radiators” whereas the AM CC rules, 15.221, is under “Intentional Radiators.” I am not sure I understand the logic for this difference,
    - May 15, 2012 at 12:00 am #26212
      
      mram1500
      Total posts : 0
      With all the chatting about Deep Voice and other CC stuff I thought “I’m gonna tune my Realistic DX-302 into the VLF band and see what I can hear.”
      WTH, it’s KDX Worldround Radio at 242 kHz. Wait a minute, I left the radio on in the garage. It’s my Plug’n Talk intercom rebroadcasting KDX.
      A friend gave me the intercoms because they didn’t work anymore. A little tweaking and cleaning and hey, they do work.
      My tweaking moved the frequency from the model “B” frequency of 160 kHz up to 242 kHz.
      The short story is I can pick it up on my DX-302.
    - May 15, 2012 at 1:03 am #26215
      
      Carl Blare
      Total posts : 0
      Wow, makes those intercoms seem even more interesting as possible short-cuts onto the LW CC spectrum.
      Hope you keep it on the air!
    - May 15, 2012 at 2:16 am #26222
      
      MICRO1700
      Total posts : 0
      242 kHz CC!
      Wow!
      How well do you get the transmission
      on your DX-302? Is it really strong?
      Is the transmission FM? Do you have
      to slope detect the signal to get audio?
      OH YEAH!
      I’m starting to build another CC coupler
      for my AM LPB CC transmitter.
      Best Wishes,
      Bruce, DRS2
    - May 15, 2012 at 3:40 am #26225
      
      Carl Blare
      Total posts : 0
      Still waiting for the parts to arrive for converting the LPB transmitter to the final frequency of 670kHz.
      After a whole weekend at 570kHz, Monday went by back on 670kHz, at 1/2-Watt!
      In late afternoon I drove up the street and the 1/2-Watt signal got very flappy and fluttery, so the lower end of the Wattage range is very sensitive for this particular system. I came home with a bag of potato chips and boosted back to 2-Watts.
      Life can only be complete with intentional radiation and carrier current.
    - May 15, 2012 at 4:12 am #26227
      
      mram1500
      Total posts : 0
      The S meter was about mid scale. Slope detecting helped a little but apparently there is enough AM component to these FM intercoms that dead on was still clear enough.
      I’m using a long wire antenna with a homebrew antenna tuner.
May 15, 2012 at 8:50 pm #26239

MICRO1700
Total posts : 0
That is really really cool!
Bruce, DRS2
- May 20, 2012 at 12:45 am #26293
  
  Carl Blare
  Total posts : 0
  Another week has passed waiting for parts to upgrade the LPB transmitter for 970kHz mid-band.
  A mysterious e-mail arrived from Mouser, the part supplier, titled : Order Status Update
  But the e-mail was a blank page with no message. It contained two attachments that had no apparent use: a GIF picture of the Mouser Logo, and a JPG picture of a Mouser Webpage where status updates are found. But of course a JPG picture is not a webpage.
  When I visited the actual Mouser site my order was simply noted as “pending.” I sort of already knew that.
  So this afternoon I returned to 670kHz temporary frequency, 2Watts, because life without carrier current is a poor excuse.
  Doggradio 2 is working on his coupler, which will be very interesting to follow.
  Is MRAM still happening at 242kHz?
  - May 26, 2012 at 6:47 pm #26332
    
    Carl Blare
    Total posts : 0
    On the upcoming date of June 4 it will be 1-month since ordering the capacitors needed to build a proper low pass filter to convert the LPB2-20 carrier to 970kHz, AM Midband. In this interim period we tried various ways of wedging into the Lowband.
    On one weekend we appeared on 570kHz, with only one guard-band on either side, and local stations nearby at 550 and 590. This was not comfortable, because the lower quality radios are inclined to blend nearby stations together, offering reduced selectivity.
    So back to 670kHz, with plenty of open space on the low side, but only one guard band at 680, then a neighbor at 690, with 1kW daytime. So we waited until the sun was behind the trees, turned on 670kHz at 2-Watts, and the 690 neighboring station dropped to 16-Watts nighttime power, and somewhat vanished. In other words, we became a nighttime station, quite unusual if not unheard of.
    But this weekend we reviewed a very interesting project done on our behalf by RFB, working in his research laboratory in Wyoming. He ran one of his LPB Lowband transmitters at 970kHz, 2-Watts, over a prolonged period, and determined that this could be done so long as the power was not increased. Having the Lowband filter running at Midband puts extra stress on the transmitter, but he proved it could be done safely.
    So we are at 970kHz, 1-Watt, playing it safe but marking our territory.
    - May 27, 2012 at 4:24 am #26334
      
      MICRO1700
      Total posts : 0
      It really is!
      Bruce, DRS2
    - May 27, 2012 at 7:25 am #26338
      
      RFB
      Total posts : 0
      “So we are at 970kHz, 1-Watt, playing it safe but marking our territory.”
      Scan for harmonics and intermod spurs and their intensity with a scanner or HF receiver.
      Hopefully those caps will arrive soon so you can make the change permanently and with the correct filtering.
      RFB
    - May 30, 2012 at 11:05 pm #26352
      
      Carl Blare
      Total posts : 0
      On the 1-month anniversary next Monday I will telephone Mouser and ask if they are still in business. Those caps have still not arrived.
      But everyday 1-Watt crippled radio station KDX CC appears at 970kHz, with a spurious buzz at 930kHz, right next to a locally licensed 920kHz.
      Today the auto went east, the direction of the powerline and neutral line from this transmitting station, and coverage was very steady, only slightly down after 2.5 blocks. Probably pumping another half Watt would help. Maybe tomorrow.
      I love the fact there are so many households in ignorance of the station right there on their dial, if they weren’t so busy texting, cell phoning, watching cable and Face Lifting. Or, what is that site? Face Box. No. Face Book? I am not sure.
      The more people who ignore my station the better.
      Well, hell, my streaming station is ignored by 7-billion people, the entire world population! Try to match that!
    - June 6, 2012 at 2:20 am #26406
      
      Carl Blare
      Total posts : 0
      What are they doing at Mouser? They aren’t sending the caps ordered 1-month and 1-day ago.
      Maybe tomorrow I’ll crank up the enthusiasm to call and track and find out.
      Meanwhile, 970kHz keeps going at 1-Watt with a mis-matched low pass filter.
    - June 6, 2012 at 8:00 pm #26413
      
      RFB
      Total posts : 0
      Perhaps it’s time to find another source. 1 month is WAY too long to be waiting for caps..from ANY vendor.
      I once ordered no longer available here in the US, some IC chips out of China, and they got here in less than 4 days.
      And they were the military grade counterpart IC’s to boot!
      RFB
    - June 6, 2012 at 10:41 pm #26417
      
      kc8gpd
      Total posts : 0
      should run 1 watt all day long into mismatched lpf’s. not quite sure what that would do for harmonic content though. rfb could probably better answer that.
    - June 8, 2012 at 12:19 am #26442
      
      RFB
      Total posts : 0
      Should run ok at the low power level. However since the LPF is configured for the low portion of the MW band, Carl’s TX is operating as if there was no LPF inline at all. The current LPF is merely providing a match to the output pair and to the output connector, but not providing any filtering as it would if the LPF were configured for the mid portion of the MW band.
      At higher levels, the configuration of that current LPF will cause the TX linear to self oscillate, and is why Carl experienced that when attempting to go above that 1 watt or so level.
      Going higher in frequency power required will be a lot less anyway.
      RFB
    - June 8, 2012 at 2:02 am #26444
      
      Carl Blare
      Total posts : 0
      Back when you (RFB) reported that I could safely run at low wattage, your estimate at that time was that it might start oscillating at about 5Watts, but I found that it goes into oscillation at 3Watts.
      Back at that time I ran for awhile at 2Watts, but this second time I’m being more cautious and only doing 1Watt, which seems to have good coverage.
    - June 8, 2012 at 10:06 pm #26460
      
      RFB
      Total posts : 0
      “Back when you (RFB) reported that I could safely run at low wattage, your estimate at that time was that it might start oscillating at about 5Watts, but I found that it goes into oscillation at 3Watts.”
      The reason why I could run up to 5 watts before self oscillation is because I tested on an AM-30 unit, which it’s low pass filter contains higher voltage rated caps in the lpf. At 5.5 it began to go into self oscillations.
      What I did not report was that same test was performed on an AM-5 unit. It went into self oscillation at 1.7 watts. Both the AM-5 and AM-30 units are rigged for the low band.
      See the reason why?
      It’s the different voltage ratings of the caps in the low pass filter. The AM-5 has lower voltage rated caps compared to the 2-20, and the 2-20 has lower voltage rated caps than the AM-30.
      The intent was to see if your CC configuration would do well at the frequency of 970Khz. Apparently it does and that is good. Believe it or not, a CC configuration is not always workable across the entire MW band. Fortunately your configuration will work with both the lower portion of the band and the mid portion without having to modify or drastically change your CC connection configuration. Saves a lot of headache and needless work.
      RFB
    - June 13, 2012 at 7:56 pm #26600
      
      Carl Blare
      Total posts : 0
      It is impressive how many themes and variations you are able to recite regarding the carrier current experience.
      Carrier current Radio 970 is doing very well everyday at 1-Watt, and I just checked on the capacitor order, for rebuilding the output filter, and so far one of nine items will be in by June 21.
      Even though the order seems unusually slow, I’m not going to complain because I am grateful a company would even have such rarely ordered items.
      I’ll be posting a picture of the setup as soon as I get some audio processing in the rack.
    - June 19, 2012 at 11:11 pm #26711
      
      Carl Blare
      Total posts : 0
      All at once when least expected I got a friendly note from Mouser about shipping the capacitors so I can build the low pass filter for the LPB transmitter operation at 970kHz Carrier Current.
      It is one day before the Summer Solstice.
      This proves that synchronicity is a word that comes to mind.
    - June 21, 2012 at 2:04 am #26731
      
      Carl Blare
      Total posts : 0
      I was fiddling with The Crow’s Part 15 Map of America and found
      The Cat – Sealy, Texas, 580 kHz CC
      bigvoices.net
    - June 21, 2012 at 9:44 pm #26740
      
      Carl Blare
      Total posts : 0
      Opened the door to get the mail and found a box from Mouser, containing the long awaited low pass filter capacitors.
      Next step, shut down the 970kHz transmitter;
      Take all apart;
      Remove low-band inductors & capacitors;
      Install mid-band inductors & capacitors;
      Slap it all back together;
      Test;
      Triumphantly return to the air.
      The whole expedition will be outlined here.
    - June 22, 2012 at 12:48 am #26742
      
      MICRO1700
      Total posts : 0
      I’m very interested.
      Please keep us informed.
      Best Wishes,
      Bruce. DRS2
    - June 22, 2012 at 3:57 am #26747
      
      Carl Blare
      Total posts : 0
      Brought the LPB up from the lower parking level, put it on the work-cart, oh by the way today I got some new LED indoor bulbs to replace the compact fluorescents and they are much better. The new light is a mood improver.
      Unscrewed the giant heat sink and unsoldered the final stage circuit card.
      Removed the low-band capacitors and toroids.
      Shut her down for the night. Will resume in the morning.
      KDX will sign on at 10 AM minus the 970 signal, and the people who anxiously search for it will begin to lose their hopes, but probably by the afternoon the transmitter will start back up and smiles will spread through the town.
    - June 23, 2012 at 1:50 am #26761
      
      Carl Blare
      Total posts : 0
      All day today all I did was examine the dismantled LPB RF Amp, study my documentation, and eventually rewind the toroids to prepare them for the AM mid-band.
      The solder points on the circuit got solder-wicked so they would be clean and ready.
      Working from left to right, four capacitors and two toroids went into place.
      The RF section got reconnected within the case, a matter of half-a-dozen wires and cables.
      The giant heat sink got re-attached, and the whole thing underwent a final visual inspection.
      Carried the LPB transmitter downstairs very carefully.
      Re installed it on its roll-around rack, RF cable, audio wires, A.C.
      Turned it on and the power level shot up to 6-Watts!
      When it was last turned off the power level had been set at 1-Watt. There was a huge improvement in efficiency.
      I dialed it down to 2-Watts and re-calibrated the coupler.
      The SWR is at an amazing 1.25:1, just a tad above perfect.
      This is the work of RFB who supplied all the data needed for this job.
      Many, many thanks
    - June 25, 2012 at 2:03 pm #26825
      
      Carl Blare
      Total posts : 0
      This week is “Low Power Week” here at KDX.
      The LPB transmitter, which ran at 1-Watt NI (Neutral Injection) before the filter upgrade, was set all weekend at 2-Watt with the new filter.
      But this morning, Monday, I dialed down to 1/2 Watt to mark “Low Power Week”
      What does it all mean?
      We have reached the stage where we are ready to bring in a professional field strength service to help us determine the permanent power setting.
      I figure that if we start at very low power, the field test engineer can call me on his cell phone and have me turn up the power until it hits the sweet spot. But I need to install a telephone down by the transmitter. I do not have a cell phone.
      In the meantime, the half-Watt doesn’t seem at all weak on house radios.
    - June 25, 2012 at 11:38 pm #26843
      
      RFB
      Total posts : 0
      “I need to install a telephone down by the transmitter. I do not have a cell phone.”
      Perhaps a “cordless” phone might help?
      RFB
    - June 25, 2012 at 11:58 pm #26847
      
      Carl Blare
      Total posts : 0
      Thank you again, RFB.
      Did I so soon forget that only recently I asked about the state of the art of cordless phones?
      Perfect!
    - July 10, 2012 at 2:25 pm #27014
      
      radioboy
      Total posts : 0
      I’m really enjoying your CC journal. I had a CC station back in the early 90’s, but had not heard of neutral loading at that time. Being on a farm, well, maybe the horses could listen. Once the signal hot the transformer out back, the signal vanished.
      Sounded great in the house, though.
      I’m really curious as to whether or not the CC setup (vs the iAM system) would be of any advantage. I’m out of the city limits on family property, so no HOAs or any of that nonsense to deal with.
      A 75 year old radio colleague of mine, who is retired, has a Rangemaster on the air now on 1610 but is wondering whether a CC would be better. I didn’t have an answer to that one! He
      lives on the coast around Lanark Village, FL.
    - July 10, 2012 at 4:33 pm #27017
      
      RFB
      Total posts : 0
      “I’m really curious as to whether or not the CC setup (vs the iAM system) would be of any advantage. I’m out of the city limits on family property”
      Although neutral loading bypasses the utility transformer and allows the signal to continue down line, you still have to make sure that signal is not exceeding 221 in band and 209 out of band emissions.
      An example. The frequency of operation is 600Khz. The formula (in feet) is 157,000 divided by frequency (600Khz) equals 262 feet (261.666666). This means that at 261 feet or so, that signal MUST hit 15uV, or the noise floor. So even if that neutral line carries your signal 20 miles down the road, the signal cannot emit any further off that line than 261 feet.
      Carrier Current is NOT a far field radio transmission system. It is a near field, or inductive field system and relies on just that, the inductive field, which anywhere within the specification called for in 221, the signal will be rock solid crystal clear, even 20 miles down line from the source point within the 261 feet from that line.
      A CC system can compliment a 219 setup. The 219 setup puts signal beyond 261 feet and into vehicle radios and portables no where near any power line or neutral line. And the CC system can compliment the 219 by sending signal directly into homes and businesses via that neutral line. Since CC is primarily a localized controlled range broadcasting method, it will make sure people who cannot pick up your 219 system will still be able to tune into your station via the CC signal coming right into their homes and businesses via the power grid wires.
      Since your out in mostly open space with some distance between your location and another, a CC system probably won’t be of any real good use except for ensuring that at night when skywave wreaks havoc on a 219 signal, the CC signal will not have that problem and folks will still get a rock solid crystal clear signal, unless you end up transmitting on a frequency that becomes occupied during the night from skywave, so pick a frequency where that will not happen if a CC system is being considered.
      RFB
    - July 10, 2012 at 5:56 pm #27019
      
      radioboy
      Total posts : 0
      You’ve provided clear information that makes a lot of sense. Thank you for the response.
      Alan
July 11, 2012 at 1:08 am #27023

MICRO1700
Total posts : 0
A commercial coupler is on it’s way.
I really enjoyed the “home made” coupler
experiment tremendously, but I would
like to really get “on the air.”
My messages might be shorter and farther
in between – I have been working 7 day weeks
recently.
And RFB, this last description you just made about
how CC works is greatly appreciated. I’m not an
engineer like you are, but reading the stuff over
and over helps me understand.
The LPB RC-6A is a joy to behold.
Best Wishes,
Bruce, DRS2
- July 11, 2012 at 1:25 am #27024
  
  MICRO1700
  Total posts : 0
  We don’t have a lot of data on these RF
  interaction problems: That is – a Part 15 station
  with an outside installed ground level
  3 meter stick/transmitter AND a CC installation
  running at the same time in the same location.
  I may be way off here, but I only know of Carl’s
  set-up. When he gets the AMT-5000 outside
  we may see some new and interesting RF interaction
  problems.
  Bruce, DRS2
  - July 11, 2012 at 3:28 am #27025
    
    RFB
    Total posts : 0
    “We don’t have a lot of data on these RF interaction problems: That is – a Part 15 station with an outside installed ground level 3 meter stick/transmitter AND a CC installation running at the same time in the same location.”
    Most of the “data” with this particular case of CC and a 219 setup operating in close proximity is pretty much just like the “data” available on practical working installs of a CC system alone from one location to the other. The “data” is site specific as is the “data” on solutions for each site’s specific problems. Most of that information is either locked up in some retired engineer’s head, some buried notebook under a pile of boxes filled with old files and books at some storage room at college USA, or has passed on into the universal CC either.
    However as we all know, putting transmitters and their antennas too close can and will cause problems. So we take basic steps to avoid that. These same steps can be taken to the installation of a CC system and an outdoor 3 meter antenna/ground plane system.
    Chances are, any interaction that will take place will be when either the 3 meter system is pushing too much power or the CC system is, which in either case alone could flood audio and/or power cabling or other nearby devices with RF. The key to remember is even at 1700Khz, the distance of the inductive field’s influence for causing reaction, or interaction issues is within the 221 spec of 92.3 feet, so if there is too much power from the CC system, interaction could and probably will happen within that 92.3 feet.
    Regardless of that, a CC system does not rely on brute force. A CC system inductively couples the RF onto the power lines or neutral line and the lines carries this signal wherever it goes until it hits a roadblock like a transformer, or end of the run of line. And besides all that, why would you want to run a CC system beyond the amount of power necessary to provide clean coverage while observing 221(157k/f 15uV/m).
    If a CC system is operated beyond what is needed, the obvious results are seriously over-driving AM radio receivers and making land line corded telephones pick up the signal and perhaps even cause the neighbor’s stereo speakers to never shut up. (har har!) 😉
    Now the same thing can happen if a 3 meter outdoor antenna/ground plane system is driven with too much power. It will produce a very strong inductive field in close proximity to that antenna. The range of interactive induction effect would depend on how much power is applied to that antenna system. Even if it was out of tune, if enough RF power is applied, it WILL produce a VERY strong inductive field and quite possibly with just the right amount of sugar and spice, everything inside that puppy hut will not be nice..like burnt arc pitted loading coil etc.
    Oh..and the same effect of over-loading AM radios within range of that strong inductive field.
    So in closing as we get back to the basics of setting this stuff up, be it a piece of wire or antenna system outside or CC system on the breaker box, planning and good judgement (the FCC calls it good engineering practices), one can reduce the potential for those new interesting RF interaction problems!
    RFB
    - July 21, 2012 at 10:10 pm #27136
      
      Carl Blare
      Total posts : 0
      AM 970 CC has been on the air part time, pending a professional field test measurement coming soon.
      There does not appear to be any interaction with the other two AMs, at 1550 and 1680.
      Even when the outdoor radial system goes in (AMT5000) it will be way in the back yard, where there are no power wires. The power line is in the front.
    - July 31, 2012 at 1:20 am #27384
      
      Carl Blare
      Total posts : 0
      As the next few months disappear into outer space, I will have tons of additions to this Journal. But let’s be simple.
      Carrier current under part 15 is complicated by the measurement requirements.
      The rules about this were written by drunk fcc attorneys and are nearly incoherent. But the way to get on in the world is to pretend.
      As the first attempt to make believe that these rules can be followed, we have ordered a professional spectrum analyzer.
      This is a large expense for a station that has no intention to reach an audience; which only operates for the pleasure of science experiment.
      In the interim our CC station is turned off most of the time, and is set at a harmless 1/2 Watts during short tests.
      The hallway monitors who track this sort of thing may be uncertain whether to pass this on.
    - July 31, 2012 at 7:58 pm #27392
      
      RFB
      Total posts : 0
      You know what Carl, you have done more to check your CC system than what most colleges did back in the hey day of CC. I see no reason why your not operating regularly.
      Fear and intimidation will be the destruction of both this nation and this hobby.
      Remember, its “Home of the Brave”..not home of the chickens.
      RFB
    - July 31, 2012 at 8:22 pm #27395
      
      Carl Blare
      Total posts : 0
      Many brave souls are homeless in the new “Homeland.”
      Intimidation is like an olympic torch that needs a good runner (as in “run away,” to quote the Telletubbies.) Torch is short for torture.
      “When they came for the part 15ers there was no one left to stand up for us.”
      Messages of Pessimism have been brought to you by CC 970, “The Downer.”
      Over on another string wildbill says he got a Sencore FS134. That sounds like something.
    - July 31, 2012 at 9:50 pm #27398
      
      RFB
      Total posts : 0
      Good meter. Such test gear shows up sometimes over on ebay and other listings.
      Here is a free tip. Keep tabs on small two way radio shops that are either upgrading their test gear or going out of business and selling off that test gear. Most of these radio shops are geared for the new digital communications and they may have some unused analog test gear sitting around doing nothing and might sell them just to get rid of them.
      Of course there are the ham fests and things.
      It’s all a matter of just how far you want to go in detail about monitoring and proofing your stations. And I can state for the world wide public record that a field agent of the FCC who inspects a Part 15 station equipped with ANY sort of testing gear to measure it’s signal, be it a field strength meter or spectrum analyzer, it impresses that field agent and clearly shows the operator taking “good engineering practices” to ensure compliance. And what else would the agent want and expect anyway?!! Everyone is happy as a fat clam.
      They are also happy if one has something to show that steps are and have been taken to be in compliance, like using the radio with the S meter and walking a parameter checking the bands for spurious etc and strength of the signal with the S meter. Document those results and keep it on file, even for 219, 209 and 239 operations.
      Proof is always in the proof…so provide some, in some form.
      RFB
    - August 4, 2012 at 9:11 pm #27482
      
      Carl Blare
      Total posts : 0
      At 4 this afternoon I switched on the CC at 2-Watts for periodic checkout, during this time while we await our final field test measurements.
      For months and months, with the coupler feeding the neutral injection method, the settings have been ultra constant for maintaining a match and keeping the SWR low. But today a surprise.
      Some different settings all of a sudden allowed lowering the SWR by quite a lot, lower than it’s ever been. This might be because two days ago I let the hose dribble outside by the RF ground rod to moisten the earth alongside the building during this drought.
      RFB has often advised keeping the ground moist for RF reasons, and it shows up big time on the tuning meter.
    - August 5, 2012 at 3:49 am #27488
      
      RFB
      Total posts : 0
      Keeping the ground moist helps conductivity with the ground rods and radials. Some setups have runs of swamp cooler hose to each ground rod and at the base, some even have the hoses ran from the base outward right above the radials buried 1 or 2 inches below the surface, adding even more help to conductivity for that return path, meaning greater peak efficiency.
      RFB
    - August 24, 2012 at 12:27 am #28018
      
      Carl Blare
      Total posts : 0
      Since wetting the dry earth three weeks ago and finding the excellent coupler response, with settings never before seen for achieving the lowest ever Standing-Wave-Ratio, things have sure changed.
      The drought has not relaxed and the earth has dried way the heck out. The standing wave is still not bad, it’s shy of 1.2:1, but all those capacitive settings that tweaked it even more are no longer there.
      What we’ll do is re-water the area to get back to that optimum state.
      But here’s an update on the carrier current experience:
      Because our carrier current radio station is still in the construction phase, it is not on the air everyday.
      Now that the carrier current station is built, and able to efficiently broadcast, the next stage of development is obtaining the field test measurements required by the part 15 rules.
      As a preface to this step, we are analyzing the signal from every means available to discover how far we are able to go with our own methods to satisfy the documentation.
      The new Signal Analyzer goes a long way toward giving us control over the signal measurement, but not quite enough.
      Meanwhile, as a test, we are broadcasting at the lowest possible setting of the LPB2-20 Transmitter, 1/4 Watt, with the high likelihood that this power level is well underneath the legal limit.
      It is also fascinating to imagine that our station might be received somewhere down the power line as if it was an out of town station.
      A DX catch, close to home.
    - October 13, 2012 at 1:02 pm #28795
      
      MICRO1700
      Total posts : 0
      There is still a lot to do.
      But it appears my signal is IN
      the power lines now, at least
      1000 feet up the street. I can
      tell because I hear nothing on
      my radio beyond the near field,
      but when I put the radio up next
      to telephone poles, the station
      audio is audible. In tests last
      spring, the situation was not
      that defined.
      The near field appears to be acceptable
      in strength as per Part 15.209.
      I don’t have a lot of time for this,
      but little by little, we are getting
      somewhere.
      Bruce, Carrier Current On 1020 kHz,
      Using An LPB RC-6A Vintage Vacuum Tube
      Transmitter From 1971
    - October 13, 2012 at 2:21 pm #28796
      
      Carl Blare
      Total posts : 0
      That is exciting, Bruce. Now you should go door to door and ask people if you can conduct carrier current reception tests in their kitchens and living rooms.
      What kind of coupling are you using?
    - October 14, 2012 at 3:04 am #28798
      
      MICRO1700
      Total posts : 0
      Hi Carl!
      There is a family down the street
      that I can go see. We are very
      good friends.
      When I can (which may not be too soon)
      I will go down there into their house
      and check the signal.
      As for the coupler:
      Well – it’s a coupler alright, but I didn’t
      say it was a GOOD coupler.
      I don’t intend to stay with this coupler –
      because it isn’t good enough.
      Here’s the deal. The transmitter goes
      into that 10 dB attenuator. So the transmitter
      is protected and it’s seeing the SWR it wants.
      After that, there really is nothing to the
      coupler. It’s just a cap and a fuse going
      into the neutral line. And that’s all. Oh –
      the transmitter is grounded in the house.
      This is an experiment. Some of my Part 15
      experiments become actual Part 15 stations
      that really get listeners. I don’t know
      what will happen with this.
      The good part about this experiment is that
      the RF is actually going down the AC line.
      Before, when I was using all of those big
      huge tuning coils, the coils were radiating
      like antennas. I did not have any clear
      indication that the RF 1020 kHz signal was
      confined to the AC line. I believe that
      set-up might have been in violation of
      Part 15.209. That’s why I did not keep it
      on the air. It was only brought on for
      brief tests and I decided I did not like
      the way things were going.
      This present coupler does not address the
      impedance mismatch between the
      transmitter/attenuator and the AC line.
      OOOOOps. I have to go. I’ll be back.
      Bruce, 1020 CC
    - October 14, 2012 at 3:48 am #28799
      
      MICRO1700
      Total posts : 0
      So anyhow – to conclude my
      above note – the transmitter
      is happy SWR wise, but the
      RF power transfer to the
      AC line is probably not
      very good.
      The set-up is now legal.
      I don’t have to worry about
      running it and it is safe.
      And the signal is now going
      down the AC line. (If putting
      the radio up next to telephone
      poles and hearing the signal is
      a good indicator.)
      But the reactance between the
      coupler and the AC line still has
      to be tuned out for efficient power
      transfer. This set-up does not
      accomplish that. This set-up is
      a lot like those longwave intercoms
      that we talked about on this thread
      a while back.
      If I don’t get the commercial coupler
      soon, I will keep working on an RF coil/cap
      inpedance match design that does not radiate.
      Gosh, I guess that’s all I have to say.
      Whew.
      Bruce, 1020 CC
    - October 17, 2012 at 2:44 am #28819
      
      MICRO1700
      Total posts : 0
      From what I can tell, my carrier current signal
      is just on my street and that’s all.
      But I’m on a very long street, and
      I think the signal is theoretically audible
      in 40 or 50 houses, and that’s with
      500 mW going into the line.
      I think I can explain why the signal
      is just on my street. Across the street
      on the other side is a high voltage distribution
      line. The way I think things are arranged –
      I believe this is why the signal is just
      on my street.
      This is acceptable to me for now.
      Because we will be moving, in the
      next place we live, it will be a
      whole different game.
      I will be continuing to work on a
      tunable coupler that is shielded
      and will not radiate.
      And if that works, I will go from
      500mW injection to 5 watts.
      As I work on this experiment, I may
      lower power by another 10 dB, from
      500 mW down to 50 mW into the line.
      That way, as I work on the coupler,
      if it radiates – it will not be a
      problem with Part 15.209. (My observations
      seem to verify this.)
      So, the long term plan is to probably drop
      power to 50 mW injection and work on the
      tunable coupler. Then I will go to 500 mW
      injection as things get worked out. Then
      I will go to 5 watts injection when things
      are ready. And then the biggest problem to
      solve is to go from 1020 kHz down to 620 kHz.
      I want to be on 620. That will be the hardest
      part.
      Bruce, 1020 CC
    - October 17, 2012 at 4:39 am #28827
      
      Carl Blare
      Total posts : 0
      The reason carrier current transmitters are built with variable power controls is that every power line match turns out differently.
      My system efficiency is so good that I’m only running 1/4 Watt, which is only 250mW.
      Bruce, if you get good coupling at 1020kHz you may not need 5-Watts.
      Use your TECSUN PL-310 to check your relative field strengths, assuming you have a way of viewing the tiny number display.
      Mine is rarely on for more than a few hours, since I’m still studying what the rules actually require.
      Still haven’t done the grass.
    - October 17, 2012 at 5:51 am #28835
      
      MICRO1700
      Total posts : 0
      Thanks for the comments about
      my new CC experiments and how
      your studies relate to mine.
      And I will take my Tecsun radio
      out and check again. That’s a
      REALLY good idea. It’s hard for
      me to see the visual display,
      but I can see it well enough.
      I am a low power
      kind of guy. I’ll be bringing
      the injection power down to
      50 mW by making another 10 dB
      attenuator and putting it in
      the line for these coupler
      experiments.
      But before I do that:
      I want to try and get over to
      my friends down the street and
      see if the signal is actually
      getting into their house. (My
      Part 15.219 signal was heard in
      their home by one of them on
      some kind of boom box radio. That
      was when I was using the Ramsey
      AM-1 transmitter modified for crystal
      control.)
      If it really is true and my signal is
      getting into THEIR residence, then, based
      on what RFB has said about how CC
      propagates down the line – and based
      on my measurements – I will have
      good reason to believe that the 1020
      CC signal REALLY IS getting into 40 or 50
      houses.
      We’ll see. I was optimistic – but
      when it really comes down to it –
      well just have to wait and see.
      Somehow it seems to good to be true.
      I’ll talk to my friends soon and get
      over there, and then we’ll know for
      sure.
      Bruce, 1020 CC
October 17, 2012 at 8:32 pm #28837

MICRO1700
Total posts : 0
My friends weren’t home.
(In case you just tuned in:)
I had gone down to a friend’s
house 800 feet away to see if
they could get my carrier current
signal.
When I saw they weren’t home, I
looked around, and noticed that
their electrical meter is on the
front of their house right next
to the front door. There was
no sound on the radio, but when
I put the radio up to the conduit
that contains their house AC line,
I heard my CC signal. This is
encouraging, because it means that
my signal is in the line that is
going to their power meter.
The signal was clear, but I don’t
know how strong it was. (I didn’t
want to hang around for any length
of time, because people would start
wondering what I was doing.) There
was also a bunch of buzz on the signal.
The AC overhead wiring on the street
is sometimes very noisy, so it made it
harder for me to assess the strength of
my CC signal.
But anyway – my signal is on the line
going that goes into their house.
Now I just have to wait until they
can have me over for a few minutes.
I’ll plug a radio in an AC socket
in their living room or kitchen, and
hopefully – the signal will be audible.
If it is, I wonder how strong it will be?
Bruce, 1020 CC
P.S. This house is 8 houses away from mine.
- October 18, 2012 at 12:51 am #28855
  
  RFB
  Total posts : 0
  “The signal was clear, but I don’t know how strong it was. (I didn’t want to hang around for any length of time, because people would start wondering what I was doing.) There was also a bunch of buzz on the signal. The AC overhead wiring on the street is sometimes very noisy, so it made it
  harder for me to assess the strength of my CC signal.”
  AC line noise, particularly on the HV lines, attracts a ton of garbage and inductively couples that junk and sends it down the lines everywhere. Then include the induced noises onto the lines by consumer devices. These “Energy Saver” squirrel tail lights and switching power supplies all add to the mix mash of noise a CC system must deal with.
  It’s not easy sometimes, as this buzz noise can be at various points along the MW band. Some rather weak, while others are very strong, and it will vary in it’s position in the MW band throughout the day and night.
  The ever changing loading characteristics of the AC utility lines is also a factor and plays in the role of how much garbage is on those lines. A CC system must deal with that as well.
  CC is a very unique form of radio transmission since it relies on those noisy lines, and can be quite difficult to work with even so and sometimes worse when confining the signal to just a single building. The building will have it’s own contribution to the headache, plus whatever is coming in off the AC mains feeding the building.
  There is no such thing as a single shot fix or solution. Every single location will have it’s own unique properties and problems. Unlike a monopole system where it can be predicted by simulation as to how the system will perform, a CC system is even more difficult to try to simulate due to the incredibly wide variable of junk on those utility lines.
  The best approach is to simply experiment and find the right combination that yields the best performance of the CC system.
  Keep at it Bruce! 🙂
  RFB
  - October 18, 2012 at 1:02 am #28857
    
    MICRO1700
    Total posts : 0
    Good to hear from you. I have
    been enjoying your progress on
    the other thread!
    I am really really enjoying this
    CC thing.
    And, I think, this is really the
    first time I have a signal actually
    going down the AC line. Before, it
    really wasn’t.
    So I will keep building on this. I
    don’t mind all the glitches. To me,
    they are part of the fun.
    I have the RC-6A open, so it can breathe.
    Those glowing tubes really look cool.
    Thanks again for your comments. I will
    very much keep them in mind.
    Bruce, 1020 CC
    - October 18, 2012 at 1:50 am #28858
      
      Carl Blare
      Total posts : 0
      Tonight at 6 PM as the storm raged and the dial was filled with static, I turned on the CC and raised the power from 1/4-Watt to 1-Full Watt.
      The dBu reading (TECSUN PL-310) at my desk on the main floor of the Internet Building went from 80dBu to 90dBu.
      Because of heavy rain I took no outdoor readings.
      This is a test mode, as I still don’t completely understand the strange trail that unfolds while trying to follow the CC rules from one point to the next.
      No matter. Just like Bruce, it is a hobby and a curiosity and a fun experience. No real business plan at all.
    - October 18, 2012 at 11:15 am #28863
      
      RFB
      Total posts : 0
      “I still don’t completely understand the strange trail that unfolds while trying to follow the CC rules from one point to the next.”
      It’s quite easy. Simply find the distance point to meet 221 away from the line, and proceed along the length of the line at the distance for your frequency per 221 to make sure the signal does not go past that distance from the line.
      Think of the line like a leaky coax, the signal can only go so far away from that line no matter how long it is.
      RFB
    - October 18, 2012 at 2:11 pm #28865
      
      Carl Blare
      Total posts : 0
      Using neutral injection I am not sure the signal is actually on the power lines, I think it’s the 3rd wire, the ground/neutral line and the earth itself are the two points and it is not obvious what I am supposed to measure X-feet from, since there are lines of all kinds going in all directions.
    - October 18, 2012 at 3:04 pm #28867
      
      RFB
      Total posts : 0
      Well the rules state distance from the source, that being the injection point. So after that, the signal should be only receivable a few feet away from that 3rd line/ground wire on the pole, which decreases the further down the line the signal can travel. If that signal has a good direct path along the 3rd line and into the drops, there is enough signal there to be received by a radio.
      RFB
    - October 19, 2012 at 1:30 am #28875
      
      Rich
      Total posts : 0
      RFB posted, in part: Well the rules state distance from the source, that being the injection point.
      Could RFB or anyone else mathematically/legally prove that the source for a compliant FCC CC system is located solely at the injection point?
      The dominant source of radiation for AM systems legally operating per Part 15 CC Rules is the a-c power line network physically nearest each AM receiver.
    - October 19, 2012 at 2:07 am #28876
      
      Carl Blare
      Total posts : 0
      Does that suggest that the CC radio station is required by the FCC to measure the radiant leakage from points near every AM receiver that is proximate to its nearest AC?
    - October 19, 2012 at 5:04 am #28878
      
      MICRO1700
      Total posts : 0
      Hi Guys!
      Yup, I am trying to figure all of this
      out. RFB’s statement seems to makes sense to me.
      That is the point where the most RF energy
      is involved. It seems to me that you would
      measure from there, and not in another place.
      That’s why he has always said that shielding
      is necessary. You want a minimal amount of
      RF to get out into the air.
      I can tell you this:
      My near field is very small. Part
      of the reason may be that only 500
      miliwatts is going into the AC line.
      Probably quite a bit less, because
      the feed is not well matched as far
      as SWR is concerned.
      (The 10 dB attenuator takes the 5 watt
      RF out from the RC-6A and drops it down.)
      (And I plan to drop down to 50
      miliwatts soon for further tests.
      That way, I can design an RF tuning
      circuit for the coupler that can
      be very small – to start. I can make
      it larger for later, when I increase
      Power.)
      (I am so conservative with my FM
      signal, it really doesn’t go
      anywhere except in the house. I
      had a friend visiting from California
      a few years ago, who also had a
      Part 15 station. He listened to
      my FM signal and said, “Gee, Bruce –
      you can let it go a little further
      than THAT.”)
      After the near field, the AM 1020 signal
      is heard next to telephone
      poles about 1000 feet east
      of my location. To me – this alone
      is a great accomplishment! Actually,
      that’s about 25 houses right
      there. (If the signal is really
      getting into those houses, and if
      it’s strong enough for a typical
      radio to pick it up and have it
      be listenable.)
      I still have not been able to
      get into my friend’s house and
      see for sure. And I have not gone
      in the westerly direction with my
      portable radio yet. The signal is
      not on the streets parallel to mine
      at all. In other words, it does not
      go north and south in any way.
      This thing is just an experiment now.
      I’m going to have to go back and read
      a whole bunch of posts and look at
      the FCC rigs to completely understand
      all of this. I also have to read
      up on theory more. I’m not the sharpest tack
      in the drawer. I have to read things
      over and over so they sink in.
      My near field complies to
      Part 15.221 (not Part 15.209
      as I mistakenly said before – and I
      made that mistake several times.)
      I’m in it for the science and to look
      at the glowing vacuum tubes and to feel
      like I’m young again. Seriously, the
      “feeling like I’m young again” is very
      important. Our family situation
      being what it is, I only have time for brief tests.
      Some day, maybe this will be a Part 15 station,
      but it probably won’t be until after we move.
      Here’s the humorous part.
      We get in the car. I tell my wife I’m
      going to track my station. We go about 150
      feet and it’s gone. Then she says to me:
      “I thought you were tracking your station.”
      And I say, “I am, but it’s in the power lines,
      and it’s not going through the air. It’s
      something else I’m trying now.”
      Then she just says, “Whatever.”
      There is another consideration here. I am
      running a 41 year old vacuum tube transmitter.
      (I do it because of my love of antique radios,
      especially those with vacuum tubes.) But – this
      transmitter might not really be able to run
      for extended periods of time. It IS old.
      If this thing continues, I may have to buy
      of build a solid state transmitter.
      Bruce, “W Sixty Hertz” 1020 CC
      P.S. The callsign W60HZ” is strictly
      for the humor. I just needed to have a
      name for this experiment.
      P.P.S. As is typical for me, this post
      is very “wordy.” I’m a motor mouth. I
      hope there aren’t too many misprints.
    - October 19, 2012 at 5:20 am #28879
      
      Carl Blare
      Total posts : 0
      You’re listening to The Motormouth of the East, from W60HZ, being heard by anyone up the pole.
      There actually used to be a station called “The Mouth of the South”, I think. It seems familiar.
      Regarding FM, try listening to your weak FM station on your TECSUN PL-310.
      My 310 has the best FM section I have ever found in a radio. My transmitters, C.Crane and Wholehouse 2.0, can be heard through the walls everywhere in the house and outdoors all around the yard. The other radios will not do that.
      If you get your CC transmitter set just right, people will think they’re getting a station a hundred miles away.
      You could even announce, “Coming to you from a hundred miles away, this is W60HZ.”
    - October 19, 2012 at 6:23 am #28880
      
      MICRO1700
      Total posts : 0
      Yup. W60HZ is a real low power
      operation.
      I am thrilled, though, that the
      signal is in the AM line, for
      some distance, anyway. This is
      something I have been trying to
      do on and off, for years. I have
      also learned more about electronics.
      This is off the topic, but I will
      briefly mention it here. I just
      listened to LPH # 56. You and Lefty
      were great, and the transmitter parade
      was hilarious!
      Oh well, back to the grind.
      Thanks again, Carl, for a great show!
      Bruce, “W60HZ” AM 1020 Carrier Current
    - October 19, 2012 at 2:07 pm #28882
      
      Carl Blare
      Total posts : 0
      Since the FCC requires “something”, I think “proof of measurement from X distance from the “source” based on frequency, I am disturbed at the thought of an inspection when I least expect it, such as while having an indoor transmitter parade.
      Meanwhile, I am learning how to actually measure something, I’m just trying to figure out what the “source” is, which I thought I knew until rich stepped in and confused the issue, all in the interest of making sure we’re legal at all times, with the caveat “you may not care.”
      But, like I say, there’s no rush. Got no epic programs that seven unknown people would probably miss anyway because they don’t scan the AM dial.
      It would be silly to receive a NOUO for a station no one ever heard.
      But it would also be silly if someone heard it.
      Bruce W60HZ has the right idea.
    - October 19, 2012 at 3:31 pm #28883
      
      Rich
      Total posts : 0
      rich stepped in and confused the issue, all in the interest of making sure we’re legal at all times,…
      Rich doesn’t want to make sure everyone is legal. He only believes that people are entitled to know what “being legal” requires, whether or not they choose to operate that way.
      The FCC rule doesn’t allow much room for confusion, IMO:
      § 15.221 Operation in the band 525-1705 kHz.
      (a) Carrier current systems and transmitters employing a leaky coaxial
      cable as the radiating antenna may operate in the band 525-1705 kHz
      provided the field strength levels of the radiated emissions do not
      exceed 15 uV/m, as measured at a distance of 47,715/(frequency in kHz)
      meters (equivalent to Lambda/2Pi) from the electric power line or the
      coaxial cable, respectively.
      But proving compliance to that rule even with a accurate field strength meter probably is impossible, because the ambient radio noise level at most locations is many times higher than the FCC limit for CC systems.
      PS: Stating reality does not constitute a “negative” post.
    - October 19, 2012 at 4:03 pm #28884
      
      MICRO1700
      Total posts : 0
      It’s all just information
      to me.
      Learn a little bit more and more,
      and apply it.
      Thanks for the info. It gives me
      more to think about.
      Because of my medical situations,
      I am loosing my house which we’ve
      lived in for a;most 22 years.
      I’m not trying to be dramatic, although
      it probably sounds that way. It will
      probably be a real good thing to start
      over.
      But getting a break from thinking about
      moving, and where we are going to go,
      and how we are going to get there, and
      how we are going to stay there – is a
      survival tactic here. We don’t have a car
      either. It self destructed due to heavy
      use over the years. My wife has a 130
      mile commute to work (both ways) every day.
      So we have to figure that out. But four weeks
      ago, the timing belt broke and blew the
      engine insides to pieces.
      After all of that, I welcome anything you
      have to say, Rich. And anything from
      anybody else.
      This is reality, too. But I sure wish it
      wasn’t.
      Best Wishes,
      Bruce, “W Sixty H Z” AM 1020 Carrier Current
    - October 19, 2012 at 4:19 pm #28885
      
      MICRO1700
      Total posts : 0
      It makes me feel really good
      to know that I am understanding
      (almost) how to build a good
      carrier current coupler.
      All I have to do is design
      it and find the parts.
      This is something to look
      forward too, no mater where
      we go.
      Bruce, “W Sixty H Z” AM 1020 CC
    - October 19, 2012 at 5:43 pm #28887
      
      MICRO1700
      Total posts : 0
      Yup. I shouldn’t have
      “gucked up” the Carrier
      Current Journal with my
      personal situation.
      A moment of weakness.
      The Carrier Current Journal
      must move on! With no guck.
      Oh CRUD! I dropped my pencil
      and the dog is eating it.
      “Hey! Doggies don’t eat pencils!
      Are you listening to me?”
      “Hey Hoover! Where are you going…”
      “No. Don’t try to eat the…”
      (Sound of kitchen table falling over.)
      “No! Not the pizza – – ”
      Maybe we have something for a
      radio comedy here.
      Bruce, “W Sixty H Z” AM 1020 Carrier Current
    - October 19, 2012 at 6:15 pm #28888
      
      Carl Blare
      Total posts : 0
      Bruce you are a wonderful radio comedy and it hurts your current carrying friends to know what you are going through. It is good, I guess, in small ways, to be able to post here and share thoughts and experiences.
      Part 15 men are purpose driven. Everything must be done to make stations happen.
      Part 15 women will be arriving any day now.
    - October 19, 2012 at 5:33 pm #28886
      
      Carl Blare
      Total posts : 0
      I was responding to the use of the word “source” as used in recent posts, and the idea that AM radios connected to “the source” were the significant measurement starting point, but as I see it now you (rich) were putting a subtle humor onto what RFB had posted when he used the term “source” rather than “electric power lines” (did that happen?).
      Heading always in the general direction of reality, I am not certain (so far) which “power lines” are being involved using the neutral injection method.
    - October 19, 2012 at 8:30 pm #28890
      
      RFB
      Total posts : 0
      “Could RFB or anyone else mathematically/legally prove that the source for a compliant FCC CC system is located solely at the injection point?”
      Sure..how about you provide the proof. Do you have such a setup and has it ever been inspected?
      By all means..educate us. Instead of going around preaching, how about a demonstration.
      Talk is cheap, actions speak a lot louder.
      RFB
    - October 20, 2012 at 2:01 am #28896
      
      MICRO1700
      Total posts : 0
      This is about 8 houses away,
      about 800 feet away.
      I’m sure they will let me in
      there once in a while to check
      if my CC signal is audible inside
      their home.
      Today luck was not with us.
      There was so much RFI in their
      house, I could barely hear WTIC,
      AM, 50,000 watts. I’ll have to
      go back another time and try
      again.
      So, this reception test was not
      a success. However, when my
      3 meter stick was up with 100 mW
      DC in, they did hear my station
      in their house. For whatever it’s
      worth.
      Bruce, 1020 CC, “W sixty H Z”
    - October 20, 2012 at 4:18 am #28904
      
      MICRO1700
      Total posts : 0
      Thank you Carl!
      The Carrier Current Journal
      must go on!
      And it will!
      Bruce, “W sixty H Z, 1020 CC AM
    - October 20, 2012 at 4:38 am #28907
      
      Carl Blare
      Total posts : 0
      The carrier current station at this location is presently an occasional test station, until I fully comprehend the beast.
      There is no intended audience, only the interest of doing it for its own sake, perhaps not an American stand point, but in any case there is no hurry to be on permanently.
      I may someday do as you did Bruce, stroll down the street placing a radio near the power poles while pretending to be on the telephone.
      Whatever happens, it is reassuring to have a carrier current station in the house.
      If I get buried in snow, I can broadcast pleas for help.
      Given a lack of AM listeners, no help will summon, but it will seem like I at least had a slim chance.
October 19, 2012 at 12:49 am #28871

MICRO1700
Total posts : 0
…On a busy street without looking
like a nut.
You have to have a radio that is close
to the size of a cellphone. Then you can
go down the street and make believe you
are talking on it. (In other words, you
are making believe the radio is a cellphone.)
Hold it up to your ear, talk into it, and
then casually lean up against the telephone
pole and listen for the signal.
I am trying to do this on a street that has
about 2000 cars going by every minute.
The cars are making too much noise.
More data to follow.
Bruce, “W60HZ 1020 AM Carrier Current”
- October 19, 2012 at 1:10 am #28874
  
  Carl Blare
  Total posts : 0
  I have pretended that a tv remote control is a cell phone, but there would be very little point in pretending it was a radio.
October 21, 2012 at 8:47 pm #28920

MICRO1700
Total posts : 0
Hello!
I enjoyed your comment.
As for the CC thing, I like just
trying to make the building blocks
work. I intend to try again at
that house down the street.
Right now, I am on a computer
that I really can’t see, so I
am going to go.
But, I’ll be back! To you people
reading this thread 5 years from
now:
There will be more experimenting.
I doesn’t end here!
Bruce, The Big Sixty Herrrrrrrrrrrtz!
- November 2, 2012 at 1:43 am #29025
  
  MICRO1700
  Total posts : 0
  I found a carrier current article
  from a 1942 QST.
  This is available on the ARRL
  website. You have to be a member
  of the organization to get the info –
  I just happen to be a member.
  Stepping back a second:
  It is fascinating to look at these old
  articles. It appears that, although
  full issues of QST are not on the
  achieve, many articles are available
  from ALL QSTs, all the way back to
  1915. (Some recent years might not
  be in the archives, I’m not sure.)
  Anyway, getting back to this CC article –
  I just started to read it. It is from either
  February or March 1942.
  In this first article that I’m am looking at,
  They are calling the CC technology “wired wireless.”
  It seems the people involved were trying to use
  power levels between 25 and 50 watts, with morse
  code. The operating frequencies mentioned here
  were in the 170 to 200 kHz range. It was felt that
  higher frequencies would not stay in the power
  lines, so the hams decided to be down on longwave.
  I need to read this article fully, and see if there are
  more articles on the CC subject. I bet there ARE more.
  It was World War 2, and I believe MOST ham operations
  were off the air, per U.S. government orders. Those
  guys loved radio just like us, and they had to figure
  out some way to communicate. CC was one of the
  answers.
  I’m going to go through the QSTs from 1942 to 1945.
  This is going to take a while. If anyone else is interested
  in looking these years over for CC info, that would be
  cool.
  In an unrelated subject from a 1945 QST, I saw a
  mention of FM BCB E skip. As we know, in those
  days, the FM BCB ran from about 42 to 50 MHz.
  However, there must have been some exceptions.
  One ham noted that he heard an FM station on
  39 MHz. I am assuming this was a broadcast
  station, and not some kind of point to point
  station, but I could be wrong. This ham also
  made note of WSM FM from that time! He heard
  WSM FM on E-skip. I do not know where he was
  located. I’ll have to try to find that note again.
  (For broadcast historians, WSM on 650 kHz has got
  to be one of the most famous AM stations.)
  Well, for what ever it’s worth. My CC set-up on
  1020 kHz continues to evolve. I will continue to
  post whatever I find in this current experiment.
  It has been fun.
  Bruce, W 60 HZ – – AM 1020 CC
November 5, 2012 at 5:10 am #29059

MICRO1700
Total posts : 0
Do to lack of eyesight, I’m
just going to summarize these.
1) 6 watts @ 50 ohms into .1 uF cap and fuse
to AC line:
Transmitter resonance light went out.
Lot’s of RF in radio room. Radio
sputtered and motorboated, although
it could have been the transmitter.
Test quickly shut off.
2) Transmitter connected to 10 dB attenuator:
So 5 or 6 watts into 10 dB attenuator and
500 or 600 mW out of attenuator
and then into AC neutral via cap
and fuse.
Resonance neon light came back on. But –
Transmitter sounded terrible. Very low
modulation. Audio distortion. I realized
ground connection had fallen off.
(Ground connection prior to yesterday was
from ground bus of attenuator to radiator
in room. I realize this is not optimum, but
it’s the best I can do now.)
3) This was changed. Ground connection still went
to radiator, but instead was attached to coax
shield at back of transmitter.
Now audio very very good. Probably 90 or
100 percent. Best I’ve heard with 1971
vacuum tube LPB RC-6A.
Went outside at 10:PM. Near field appears
to be compliant with FCC Part 15.221.
Transmitter audio signal heard
over clutter on frequency 1000 feet down
street in easterly direction. (Next to telephone
poles.)
Transmitter heard at least 1500 feet in westerly
direction next to telephone poles. At one point
signal faded way up about 1000 feet away. Don’t
know why.
No coverage on any adjacent streets except for
first telephone poles on a few. So signal
seems to be going down the line covering a
2500 foot line just on my street.
This is the best so far, and impedance matching
network has not been built yet. I have learned
a lot and I feel I will be able to build a coupler
eventually.
Note: Just before they went out of business, LPB
was trying to figure out how to build a coupler
that would adjust for changes in line impedance.
I have some ideas in this area.
Getting somewhere.
(There has been a lot of talk on various boards
about putting the Ramsey AM-25 onto carrier current.
This would include a power increase mod (or mods)
to permit 1 or 2 watts.) Sounds like what the
doctor ordered to me. Maybe somebody will try it.
Best Wishes,
Bruce, W 60 HZ – – 1020 kHz AM CC
- November 5, 2012 at 5:24 am #29060
  
  Carl Blare
  Total posts : 0
  Tonight I ran a CC test at 1/4 Watt (250mW) and the signal in the building was 60dB over 5, as I think is the proper way to read an S meter.
  What I need to get down on paper is a map showing where the power transformer actually feeds. I am the last house on the west, but the transformer appears to feed lines for quite some distance east to houses on both sides of the street.
  Using neutral injection with a dedicated ground rod involved in the system it is unclear to me whether this arrangement is limited to the power lines on my one transformer out on the pole, or whether neutral and associated ground lines also distribute to other power transformers.
  What I am trying to say, is that I don’t know where to go to grab the key field strength measurements to assure compliance.
  Test ending. Shutting off.
November 5, 2012 at 5:45 am #29061

MICRO1700
Total posts : 0
Does anybody have any specifics on this?
I guess the theory is that you get a
little power transformer – say 6 volts
or so, and (via variable resistors, fixed
resistors, and maybe a phase forward and
reverse switch) you can cancel out the audio
hum (or lower it) from your CC system.
You take the parts, put them together, and
get the AC potential down to audio line voltage.
Then you feed it into your audio line somewhere
before your CC transmitter. You adjust the
phasing and remove the hum.
This sounds like it could be helpful and fun to build.
Has anybody done this? I feel like I’ve heard it
before.
By the way, I do not have much of a hum problem here.
Bruce, W 60 HZ – – 1020 AM CC
- November 5, 2012 at 6:50 am #29062
  
  Carl Blare
  Total posts : 0
  That should read, “What I think I’ve seen.”
  In the carrier current long wave intercoms from Radio Shack the circuits appear to have coupling transformers with a winding that is center tapped in the way that places one side out of phase with the other, probably for hum cancelation.
  But in the couplers for the LPB and Radio Systems CP-15 I do not find any phase canceling circuitry. The toroid transformers look like they mainly provide impedance variations, and the capacitor banks provide filtering and further matching.
  - November 5, 2012 at 7:33 am #29063
    
    MICRO1700
    Total posts : 0
    And now our next episode –
    - November 5, 2012 at 8:02 am #29064
      
      MICRO1700
      Total posts : 0
      Just when you thought it was OK to
      go back into the pool, it’s full of RF!
      OR
      The final solution – really isn’t!
      Last time as you remember, things with
      the CC stuff were looking good.
      “Hey Choncey, look at that moose with
      the carrier current transmitter. Is he doing
      a remote of the game?
      I don’t know, Edgar. Why don’t you
      finish pulling your sweater over your head?”
      “Why should I do that, Choncey? The game hasn’t
      started yet.”
      Oh, I don’t know Edgar. Here come
      the cheerleaders!
      NO OH! SOMETHING WENT WRONG, AND JUST WHEN
      HE WAS THINKING OF STARTING DAILY PROGRAMMING
      ON 1020.
      Putt putt putt (RF feedback) 6AL11 gone crazy?
      Stay tuned for our next episode:
      THE FINAL REALLY ISN’T – GET THE HAMMER
      OR
      7 SOLDERING IRONS, BUT NO SOLDER
      (sour sound of horn blowing)
    - November 5, 2012 at 9:09 am #29065
      
      MICRO1700
      Total posts : 0
      A lot of testing. I think the transmitter
      is OK. Things had gotten real unstable.
      I just couldn’t go to sleep. I had to work
      on it.
      6 watts into the dummy load. Good modulation
      now. We’ll see. (I was thinking about doing
      some REAL (!) programming from 6:AM until sunset.
      That way, the old beast would have time to
      rest at night. You know, like a daytime only
      station.) I had that idea to proceed with programming
      because things had gone so well.
      So it must be the attenuator/coupler.
      ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
    - November 5, 2012 at 10:46 am #29068
      
      RFB
      Total posts : 0
      “A lot of testing. I think the transmitter is OK. Things had gotten real unstable.”
      It probably is ok if it’s running fine into a dummy load. This leads to question the coupler itself, a home made coupler which most likely does not have enough isolating between TX and the load, thus your seeing those shifts in load characteristics in the TX. Not good.
      Such wild shifts can swing things so far off kilt that even that tube TX may get damaged. Tube might be king but I have yet to see a tube that is 100 percent invulnerable. Wide tolerance yes, but invulnerable..no.
      Tube are very high impedance devices, thus subject to more outside influence such as loading characteristics that shift. In today’s modern world, tubes are only good up to a certain point, then they become pretty darn ridiculous in what is required just to have them glow..much less do actual work.
      Keep at it though Bruce…I would focus on the coupler and it’s isolation ratio, but also keep in mind that the more you increase the isolation ratio, the more you dampen the coupling efficiency ratio too. Find the balance and work around establishing a “window” of operation with that balance. You will find that you will have to sacrifice one for the other, and vise versa, but you can find that balance between the two and have a workable coupler.
      RFB
    - November 5, 2012 at 3:11 pm #29070
      
      MICRO1700
      Total posts : 0
      This is a blast.
      I am enjoying it immensely.
      I’m going to run the transmitter
      through a dummy load all day to
      check it. The watt meter will be
      on it with the load, and we’ll put
      music through it.
      I’m going to take the coupler apart
      and put it back together.
      This may take a while.
      I have a “ferrite” loopstick antenna
      salvaged from a
      radio I just took apart. Could I
      make a matching transformer from
      that and put it in a shielded box?
      It’s small. I have small shielded
      boxes.
      You guys, I have to read all of your
      notes again.
      Thanks again,
      Bruce, W 60 HZ
      P.S. I have no $$ to spend, so I thought
      I would try this just for fun. If I could
      get a hold of some torriods I would – but
      that’s just not possible right now.
    - November 5, 2012 at 3:13 pm #29071
      
      Carl Blare
      Total posts : 0
      The Carrier Current Testing Station is on this morning.
      I set the power output as low as possible before cut off and it’s so low on the meter in the coupler that I think it’s equivalent to a 100mW part 15 transmitter.
      Upstairs on the desk the S meter still reads a healthy 60dB over 5, full scale.
      The signal analyzer screen shows 38dBm, making my peak equal to the signal I get from a 5kW station located 1-mile away.
      My ambition is to be receivable in the area as if I was coming from some far distant town.
      I might get together with Bruce MICRO1700 dog leg studio and make up a fictitious town somewhere.
      “This is station GWIZ, Gee Wizz, coming from Tent City, Arizona. We broadcast at 980 on the dial, but we’ve slipped to 970 because of a missing dip switch.”
  - November 5, 2012 at 10:08 am #29066
    
    RFB
    Total posts : 0
    “In the carrier current long wave intercoms from Radio Shack the circuits appear to have coupling transformers with a winding that is center tapped in the way that places one side out of phase with the other, probably for hum cancellation.”
    That’s right. Two windings with a center tap serving two purposes…60hz buzz cancellation and coupling.
    “But in the couplers for the LPB and Radio Systems CP-15 I do not find any phase canceling circuitry. The toroid transformers look like they mainly provide impedance variations, and the capacitor banks provide filtering and further matching.”
    That’s because the toroid transformers themselves do more than just coupling. They provide that 3000:1 isolation ratio which is what eliminates the hum buckling.
    The toroid arrangement is what also provides the nifty isolation from the load and transmitter so that shifts in the load inductance does not affect the loading of the transmitter, or the coupling efficiency.
    RFB
November 6, 2012 at 4:57 am #29072

MICRO1700
Total posts : 0
Thank you for all the great comments.
W 60 HZ ODDS AND ENDS DEPT.
Transmitter has been running for
a least 12 hours on the dummy load.
It sounds great. Whew. I’m glad it’s
OK.
I have a possible explanation for what
happened last night. This will explain
itself.
I believe this LPB RC-6A was built for
540 to 1000 kHz. I tried to put it onto
1020 kHz, and when I first went to do that,
I had trouble. The tuning coils and caps
are right on the edge. Then, for some unknown
reason I was able to get it working on 1020.
I think the adjustment is very critical, because
it is on the edge. I believe the coil might have
slipped again last night (because I moved the
transmitter to work on it.) When it slipped, I
lost resonance.
There’s an other thing. I moved the coupler, too.
It may have a broken connection in it somewhere.
I won’t experiment with it again until it’s
completely checked out.
I talked to my friend today about that commercial
coupler that he had. I guess the story is that
he can’t find it. I sure can’t fault him. He
has given me so much old gear from radio stations
that were throwing things out. If he finds the
coupler, fine. Otherwise, I’m content to experiment.
RFB, I remember your kind offer to sell me a coupler.
Someday maybe I’ll have some money. It won’t be for
a long time. If you end up selling it to somebody
else that will be fine. If you decide to keep it as
a backup, that’s fine, too. Meanwhile, my friend will
keep an eye out for the coupler.
I was almost on 970 kHz last night. Actually, I
was, but not for very long. I had a crystal for
970 which I had never tried. Turns out it wouldn’t
start. It would kick into oscillation and then die.
Then it would repeat that over and over. It also
ran very very warm, almost hot. Too bad, too. Carl,
970 wasn’t as good a channel as 1020, but the
transmitter liked it better. I got good resonance
on the TX neon bulb indicator.
Carl, we could have called ourselves, “The 970 stations.”
You and me.
That’s it from here.
It’s funny, I think I mentioned – I was just about
to go 6:AM til sunset on 1020 CC with programming,
because it seems like a signal was getting out into
the grid pretty far. I guess there’s
a lot more to do before that happens.
Bruce, “The 970 that almost was.”
- November 6, 2012 at 12:24 pm #29073
  
  RFB
  Total posts : 0
  There is a TCU-30 coupler up for auction on ebay..
  TCU-30
  ..and an LPB AM-30 transmitter by the same seller..
  LPB AM-30
  RFB
November 6, 2012 at 12:34 pm #29074

MICRO1700
Total posts : 0
This is great because it means
other people are interested in
CC.
I hope it works out well for you.
Best Wishes,
Bruce, W 60 HZ
- November 6, 2012 at 3:25 pm #29075
  
  RFB
  Total posts : 0
  Sorry if you misunderstood, I posted those links since you mentioned about a coupler. I did at one time have one to sell but that is already gone and the ones I have aren’t going anywhere except into service…once I find a location for them that is!
  I’m not the seller nor interested in bidding on those things. But your correct, there are others out there interested in CC. Usually when an LPB item shows up at auction..it isn’t there for long, and expect quite a good number of bidders going after it/them.
  RFB
November 6, 2012 at 4:14 pm #29076

MICRO1700
Total posts : 0
I went down to a friend’s house
14 houses down the street.
It was an spontaneous thing.
I had a Grundig S-350 with me.
I didn’t expect any results.
But I can hear my station in her
house on my Grundig S-350. It’s about
1000 feet away, and like I said – about 14
houses.
It was a battery powered radio. the signal
only came in on the side of the house where
the power line comes in. So that’s proof
that this is working CC, and not going
through the air.
The signal was not that strong, but again,
this is just the beginning! When the time
is right, I will go back with a “plug in to the AC”
radio.
This is a BIG deal for me.
Best Wishes,
Bruce, W 60 HZ
“W 60 HERTZ! IT ACTUALLY WORKS!”
- November 6, 2012 at 4:39 pm #29077
  
  Carl Blare
  Total posts : 0
  That was very rewarding to hear your CC signal on the radio in the neighbor’s house…. you are rewarded for your design work.
  Thanks RFB for posting the LPB stuff. I went and looked at it for 15-minutes while I debated whether to bid, but I made a decision that 30-Watts is way more than I need and that for my 2nd CC venture, which will be a daytime only station at 660kHz, I will probably build about a 5-Watt transmitter.
  I know this has been covered before in conversations with RFB, but I am going to repeat the whole process because I am fascinated by the subject…..
  I once asked if I could inject two CC signals into the same electric service, with two transmitters and two couplers, by connecting one by neutral injection and the other by power-line injection.
  I know that your answer was that a mixing-circuit would be needed to isolate the two signals from getting into each other’s transmitters, BUT….
  Elsewhere you said that the torroids prevent AC hum from backing up into the transmitters, therefore, wouldn’t the torroids also prevent RF signals from backing up into the transmitters?
  - November 6, 2012 at 8:06 pm #29082
    
    RFB
    Total posts : 0
    What your looking for is a combiner, except with the connection configuration your proposing, that combiner would have to reject the signal on the neutral but at the same time allow the other to use that neutral as a return.
    Be a lot easier to just combine and reject each signal to the other and feed it all into the neutral.
    The other way would be like expecting a vertical monopole to be a ground plus a radiator. Similar setups such as an MW tower with an FM hung on it, the notch/tuner does something similar to what you will need for your neutral/hot two CC setup.
    RFB
    - November 6, 2012 at 8:18 pm #29083
      
      MICRO1700
      Total posts : 0
      Carl, with 2 signals, you
      might have to share time.
      This is a joke, of course.
      What RFB is saying is right.
      This does remind me of 3 or 4
      stations in Chicago that shared
      1240 for decades. 3 or 4 separate
      transmitter sights, 3 or 4 antennas,
      whatever it was. It’s an amazing story
      anyway.
      Yup, I’m happy about this result. It’s
      very very interesting.
      Bruce, W 60 HZ
    - November 7, 2012 at 4:42 am #29084
      
      MICRO1700
      Total posts : 0
      I’m thinking of actually going back
      on the air. For starters – Saturday
      and Sunday from 6:AM to sunset.
      I’m thinking about this because of
      today’s success with the CC set-up.
      I have the potential to have an
      audience now.
      I made one change with the coupler.
      I have some notes sitting around here
      that are very old. These notes mention
      loading up the AC line with a 10 uH
      inductor. Theses notes said the coil
      would have around 37 ohms of reactance
      on the AM BCB. But the frequency is
      unknown. I put a 10 uH coil in anyway.
      (I made it.) Out at the telephone poles,
      the signal might be a little louder, it’s
      hard to tell. The coil did not make
      things worse. I did notice one thing.
      Before, the clock radio upstairs was just
      hum when I tuned into my signal. Now the
      hum is very low and there is a lot more
      audio. The hum on the portable radio in
      the house is less, also. I have no idea what that means.
      Here is my stupid question. It concerns the
      above 10 uH coil. First of all, at 1020 kHz,
      it’s reactance is probably not 37 ohms.
      Also, shouldn’t the reactance be tuned out
      somehow? I thought reactance was an
      undesirable factor in all of this.
      More ideas to come.
      Bruce,
      W 60 HZ – – AM 1020 CC
    - November 7, 2012 at 6:02 am #29085
      
      MICRO1700
      Total posts : 0
      at the telephone poles.
      Now to put this hot little
      transmitter into shut down.
      Bruce, W 60 HZ 1020 AM CC
    - November 7, 2012 at 6:13 am #29086
      
      MICRO1700
      Total posts : 0
      Don’t worry RFB. I’m
      not going to stop developing
      this coupler. I will keep
      working on it.
      How do you measure SWR on the
      line side of the coupler? Do
      you just use a regular SWR bridge,
      or is there some other way to do it?
      Bruce, W 60 HZ
    - November 7, 2012 at 1:42 pm #29088
      
      MICRO1700
      Total posts : 0
      More adjustments.
      So here I am outside in
      my goofy bright yellow raincoat
      trying to look discrete.
      Going up to telephone poles, checking
      the readings on my Tecsun PL-380.
      1000 feet away, the reading on the
      PL-380 is 63 dBu and 25 dB S/N
      ratio, whatever that means. (I know
      you guys have explained this stuff,
      but I have to look it up all over
      again.)
      But I guess what I’m trying to say is:
      1000 feet away on that telephone pole,
      the reading on the PL-380 is as high
      as it can go. At the telephone pole
      beyond that, there is NOTHING. Interesting,
      huh?
      I yelled “good morning!” to the guy at
      the bus stop, about 30 feet away.
      He turned and looked in the other direction.
      Bruce, W 60 HZ
    - November 7, 2012 at 2:41 pm #29089
      
      Rich
      Total posts : 0
      Going up to telephone poles, checking
      the readings on my Tecsun PL-380.
      1000 feet away, the reading on the
      PL-380 is 63 dBu and 25 dB S/N
      ratio, whatever that means. (I know
      you guys have explained this stuff,
      but I have to look it up all over
      again.)
      Bruce, under FCC §15.221, a carrier current system operating on 1020 kHz is limited to a maximum field intensity of 15 µV/m at a distance of about 154 feet from the a-c line.
      That field intensity is below the r-f noise level outside of a screen room. An AM signal having that value of field intensity would be unusable to AM receivers located in a normal listening environment.
      I have a PL-310, which uses the same microchip as the PL-380, and provides the same display of “signal strength” and S/N. When I tune it to 1040 kHz (daytime) it picks up WHO Radio from Des Moines — who has a known field intensity of about 500 µV/m at my location. The PL-310 display shows 27 dBµ with a S/N of about 10 dB, with the receiver oriented for highest readings.
      So if your PL-380 is receiving a 63 dBµ signal with a S/N of 25 dB when located 1,000 feet from a radiating power line, this will give some “calibration” to the performance of that system with respect to FCC §15.221.
      Hope this post is not considered to be “anti Part 15.”
    - November 7, 2012 at 4:43 pm #29092
      
      RFB
      Total posts : 0
      “Bruce, under FCC §15.221, a carrier current system operating on 1020 kHz is limited to a maximum field intensity of 15 µV/m at a distance of about 154 feet from the a-c line.”
      That’s right. But I will guarantee you this…if his signal is a few microvolts above 15 at 154 feet, the FCC isn’t going to stop the press and break out the violation pad…not when they got 16 year repetitive licensed violator/s committing fraud and perjury.
      Bruce is working with a home made coupler, so he is bound to get a signal strength a bit more than normal from a commercial coupler and the fact that the signal is without a doubt radiating from something more than just the utility lines.
      He is still in the discovery/experiment mode.
      “Hope this post is not considered to be “anti Part 15.”
      I don’t think it is. I think it’s a good refresher for those already well aware of the limits for 15.221, or any other Part 15 rule. I don’t know if the newbies would find it useful though. :p
      RFB
    - November 8, 2012 at 12:04 am #29102
      
      Rich
      Total posts : 0
      Submitted in this thread by “RFB” on November 7, 2012 – 11:43: …But I will guarantee you this…if his signal is a few microvolts above 15 at 154 feet, the FCC isn’t going to stop the press and break out the violation pad. …
      I agree with that, RFB. But let us do a little more math to see what the field at 154 feet might be for the scenario reported in this thread.
      This particular carrier-current system reportedly produced a signal indication of 63 dBµ on a Tecsun PL-380 receiver tuned to its frequency, when located 1,000 feet away from the nearest a-c conductor that this c-c system was driving.
      In an earlier post in this thread, I reported that a known field intensity of about 500 µV/m produced a signal strength reading of 27 dBµ on a Tecsun PL-310, on a frequency only 20 kHz away from the reported frequency used by this c-c system. The PL-310 uses the same microchip as the PL-380.
      The 36 dB difference between these two indicated voltages is a ratio of 63:1. In other words, the PL-380 was indicating a field intensity from that c-c system at that location of 63 x 500 µV/m = 31,500 µV/m.
      If the field from this c-c system is 31,500 µV/m at 1,000 feet from the nearest a-c conductor, then the 1/r field at 154 feet from that a-c conductor is 1,000/154 x 31,500 µV/m = 204,545 µV/m.
      Probably most would agree that this exceeds the 15 µV/m limit of §15.221 for a distance of 154 feet by a lot more than “a few microvolts.”
      Part 15 Rules appear simple, but both their underlying physics, and compliance to those Rules are far from simple to grasp and implement — especially for “newbies,” and maybe even for some who are not.
      But then, those are the people who can most benefit from the posts in this thread.
    - November 8, 2012 at 12:53 am #29103
      
      Carl Blare
      Total posts : 0
      The calculations presented by rich are highly interesting in the difficult science of measuring for carrier current compliance, but let’s explore further.
      If I read correctly, and it’s possible I may have overlooked something of what was said by Bruce in his description, but I think he said he was measuring “distance from the pole”. But that doesn’t really explain where the overhead wires were located.
      We may have a situation here, where because of Bruce’s eyesight condition he may not have been able to ascertain the location of the overhead wires, or, as could happen with anyone, be absolutely sure that the overhead wires were actually part of the carrier current path.
      Therefore, his reading might not have been the required “distance from the wires” that have significance in grabbing a meaningful field reading.
    - November 8, 2012 at 3:43 am #29105
      
      RFB
      Total posts : 0
      “Probably most would agree that this exceeds the 15 µV/m limit of §15.221 for a distance of 154 feet by a lot more than “a few microvolts.”
      I don’t think it’s “probably”, more like all would agree it’s over the limits.
      But let me make a point that Bruce is experimenting and learning as he goes. Since Bruce is most likely not going to have precise measuring gear, and the added fact the coupler being used is home built and under test, and that Bruce is not leaving this testing signal on for hours and hours, but long enough to test and measure, I would think that “probably most” would look at the field strength reported as part of the experimentation process that Bruce is currently undertaking and that it is not “broadcasting” to any degree.
      Your information will help Bruce along with the development of his home built CC coupler. I’m confident that when Bruce has it perfected, it will meet that limit just fine.
      Continue experimenting and measuring Bruce.
      RFB
    - November 7, 2012 at 2:46 pm #29090
      
      Carl Blare
      Total posts : 0
      The reason that the guy 30-feet away turned in the wrong direction when you shouted good morning was that your voice carried past him, bounced off a wall on the other side, and came back. You accidentally used ventriloquism.
      The second number on your field strength reading, 25, is full quieting on the AM band. That’s the S/N, the “signal-to-noise”, and on the AM scale 25 is maximum signal above noise. That is good.
      The other reading, the field strength, 63dBu is very good. Compare it to full power stations in your area. They will probably range from the 30’s up through the 60’s, unless they’re very near by, then they could get up into the 80’s. Anything in the 90’s means you are in the transmitter shack.
      Also, for comparison, get a field strength reading near your transmitter.
November 7, 2012 at 5:55 pm #29094

MICRO1700
Total posts : 0
Thank you so much you guys.
And Rich, it’s all good. Nope,
your statement is not anti Part 15.
Yeah, this is an evolving coupler.
As long as it doesn’t turn into
a tyrannosaurus rex, I think I’m OK.
(Have you ever tried to clean up
after one of those things.)
I must have been sheer luck that the
coil I made loaded up the AC line
in what seems to be – close to what
I am looking for.
After the near field, there is some
radiation from the power lines, and
then it completely goes away.
I believe I’m compliant. Still:
With me, it’s “test test test.”
Drives my wife crazy.
Bruce, W 60 HZ
- November 7, 2012 at 6:08 pm #29095
  
  MICRO1700
  Total posts : 0
  I want this to be a really
  good coupler.
  We will be moving and I want
  it to work wherever we end up.
  So I plan for it to be very
  much like a commercial one
  when it’s done.
  This will take a while. I want
  to learn about this stuff, mainly.
  If I can build one, I can build
  several. How’s about if a logic
  circuit switches between couplers
  to the best one for the situation
  that comes about when the line
  impedance changes.
  Or just throws relays into some
  different parts in the cabinet.
  My RC-6A has a bright neon light
  that indicates when the system is in
  resonance. Right now, that light
  is shining brighter than I have ever
  seen it. Put a photo cell next to
  it… Feed that to a logic circuit…
  You’ve got a control system to
  follow line Z changes.
  Will it work? Who knows? I will
  probably never get that far.
  Bruce, W 60 HZ
  - November 7, 2012 at 6:54 pm #29096
    
    MICRO1700
    Total posts : 0
    Last night, I was going
    to measure a section of
    sidewalk, and then use
    that as a reference to
    figure out distance.
    This would be to check for
    compliance and other things.
    But there were too many people
    around. I was going to go out
    today, but we are getting a storm
    with snow and sleet and rain, and
    other small particulate water things.
    It will have to wait.
    This is getting more and more
    interesting.
    Bruce, W 60 HZ
    - November 7, 2012 at 7:46 pm #29098
      
      Carl Blare
      Total posts : 0
      That weather you are getting on your side walk must be the Nor Easter.
      I think I know what that means….
      Carl celebrates neither christmas nor easter.
      Then it snows and the wind blows.
      Would you people mind stepping off of this particular side-walk square so I can measure it? I’m with the sidewalk inspection office.
    - November 8, 2012 at 4:46 am #29106
      
      MICRO1700
      Total posts : 0
      That guy must have thought I
      was nuts. (And now I have to
      go back out there and measure
      the sidewalk.)
      He must have seen me walking
      down the street putting that
      PL-380 next to the phone poles.
      But the weirdest part of all of
      this was going down to my friend’s
      house and actually hearing my station.
      I don’t know if I told the story completely.
      We were talking in her kitchen and she said,
      “well… why don’t you turn on your radio
      and see if you can get your station?”
      So I did and there was nothing. I was
      disappointed but not too much. In Part
      15, this is a regular occurrence!
      Then I started walking toward her living
      room. And she told me that she heard a
      little bit of music. It was very weak.
      I still didn’t think it was my transmission.
      But as I got more into her living room,
      it got louder. I kept walking toward the
      strongest signal. I got to a “sitting
      window.” I guess that’s what you call it.
      It was a corner sitting window, so the
      flat area was a big corner and so was the
      window. Bull’s eye. The signal was the
      strongest there. And that’s the side of the
      house where the power line connects,
      although up higher on the side of the
      house, of course.
      I set the Grundig S-350 on the big window
      sill and we went back into the kitchen and
      she and I talked for a while.
      The signal wasn’t perfect, but it was
      completely listenable. And we talked,
      and listened to it for about 30 minutes.
      Then I went home. I am fortunate to
      have some good friends in the neighborhood
      on this busy main street.
      We all brought up our kids together here.
      This took place before I did mods to the
      coupler last night. So the signal there
      is probably stronger now. However,
      I won’t be going back there for a while.
      I don’t want to wear out my welcome. i
      will probably go back in a few weeks.
      So it was house number 14, probably
      about 800 or 900 feet away.
      What a great experience!
      Bruce, W 60 HZ
    - November 8, 2012 at 5:45 am #29107
      
      MICRO1700
      Total posts : 0
      I just caught some of your comments that
      I didn’t see before.
      I’m about to go to bed.
      But I will have a few responses tomorrow.
      Thanks a lot you guys!
      Bruce, W 60 HZ
      P.S. It’s funny, I have a friend who really
      likes the callsigns: W117VAC or W120VAC
      or W125VAC.
      It’s all alphabet soup to me!
    - November 9, 2012 at 4:55 am #29114
      
      Carl Blare
      Total posts : 0
      (a) Field strength levels of radiated emissions from carrier current systems may not exceed 15 uV/m, as measured at a distance of 47,715/(frequency in kHz) meters from the electric power line.
      Here’s my interpretation.
      15uV is not the reading being sought at X distance.
      15uV is to be DIVIDED by the distance, which is derived from the distance portion of the formula. In other words, there are two formulas.
      At my frequency of 970kHz the distance formula gives me 161.3 feet from the electric lines, (49.19 meters) and when this distance is divided into 15 uV the result is .304 uV.
      The expression “15 uV/m” is a division operation.
    - November 9, 2012 at 11:02 am #29116
      
      Rich
      Total posts : 0
      15uV is not the reading being sought at X distance. The expression “15 uV/m” is a division operation.
      The unit of measurement “µV/m” refers to the radiated r-f voltage existing between two points in space separated by one meter.
      In carl’s case, FCC §15.221 permits a field strength not exceeding 15 µV/m between two points in space separated by one meter, at a distance of 161.3 feet from the nearest a-c conductor driven by the c-c transmitter.
      But as mentioned earlier, a 15 µV/m field* in the AM broadcast band is well below the ambient r-f noise level in almost all radio listening environments. So if a c-c system can usefully be received on an AM receiver over 100 feet away from the nearest a-c line, probably that c-c system is non-compliant with FCC §15.221.
      * let alone a 0.3 µV/m field
    - November 9, 2012 at 12:45 pm #29117
      
      Carl Blare
      Total posts : 0
      A forward slash between two figures in mathematics conventionally signals a division operation.
      If 15 uV/m is not a division problem, but the following figures, 47,715/frequency in kHz is a division operation, it would be the case that the FCC is using non-standard and confusing symbolic language only understood by insiders.
      Most part 15ers, as hobbyists, are made outsiders by the dancing language in the Part 15 Rules, written partly for the comprehension of the unschooled hobbyist, but at intervals written for trained insiders making the practice of the part 15 hobby treacherous and unlikely to be compliantly achievable.
      rich is not “anti part 15”. The Part 15 Rules are anti hobbyist.
    - November 9, 2012 at 3:55 pm #29118
      
      MICRO1700
      Total posts : 0
      By the way, my near field looks pretty
      tight.
      My dog Hoover got out into the busy
      street, which is bad. The only way to
      get him is to open the car door and
      then he thinks he’s getting a ride.
      My dad and I did this in the driveway,
      Hoover jumped in, and we had him contained.
      (Thankfully, it was almost disaster.)
      Then we decided to go around the block. We
      went right out of the driveway.
      I heard the signal on 1020 for a few houses.
      (The signal rides a power line on the right
      side of the street.)
      We drove around the block. (The signal abruptly
      vanished when we turned right to go around.)
      We went around and there was nothing. Then we
      came around toward the house from the
      left. I didn’t hear anything until we got
      into the driveway.
      Gee, I hope nothing’s wrong. I’m going to have
      to go out to the poles again.
      Bruce, W 60 HZ
    - November 9, 2012 at 4:47 pm #29119
      
      Carl Blare
      Total posts : 0
      Everyday I am learning new things about the poles along the street. There is a pole in front of every house in some cases, and in other cases there is a pole at every other house.
      I notice one house, two doors from here, that has no electric lines from the pole. It must be getting power from the rear or perhaps underground.
      Houses on the other side of the street mostly get power from this side of the street, as there are no poles over there, except an occasional pole here or there.
      Are power wires not connected to my same transformer of any interest?
    - November 9, 2012 at 6:33 pm #29124
      
      MICRO1700
      Total posts : 0
      I went out again.
      The readings on the poles were lower
      today, but still very very good.
      It’s gonna change all the time.
      Best Wishes,
      Bruce, W 60 HZ
    - November 9, 2012 at 8:05 pm #29125
      
      kc8gpd
      Total posts : 0
      http://www.gregssandbox.com/wocr/index.htm
    - November 10, 2012 at 1:25 am #29126
      
      Carl Blare
      Total posts : 0
      By studying CC at the pixel level I’m slowly gaining a sense of what’s happening.
      Trips in the automobile listening to a silent carrier are informative, because I can listen for that moment when sputter noise starts to overtake the signal, and there is a quick drop-off at that point, which seems like the “edge” of the CC signal.
      By increasing power from 1/4W up to 1Watt there is no doubt the near field increases according to every indication, i.e., field strength meter, peak as viewed on a spectrum analyzer….
      But interestingly the “edge” only increases by a small amount.
      I will continue trying to attract a clear explanation of how to decipher the actual part 15 rule for determining the outer boundary, rather than some virtuoso math with no followups to further dialogue.
      By now readers are reaching for the mouse, but I’ll be back.
    - November 10, 2012 at 2:18 am #29127
      
      Rich
      Total posts : 0
      I will continue trying to attract a clear explanation of how to decipher the actual part 15 rule for determining the outer boundary, rather than some virtuoso math with no followups to further dialogue.
      The specific followups apparently sought by the poster of the above clip might more readily appear if that poster had provided, or could provide technical justification for others to post such followups.
      The math posted previously in this thread is not virtuosic, just that taught in primary school.
      Learning when such (simple) math is appropriate to analyze/predict r-f propagation is a different matter, however — usually requiring many years of study and experience.
    - November 10, 2012 at 2:21 am #29128
      
      Carl Blare
      Total posts : 0
      “Learning when such (simple) math is appropriate to analyze/predict r-f propagation is a different matter, however — usually requiring many years of study and experience.”
      There’s your virtuosity. And bravo.
    - November 10, 2012 at 1:14 pm #29129
      
      kc8gpd
      Total posts : 0
      carrier current is near field wired/wireless. that is to say for the most part if you are within about 50 foot of the line or plugged into the line you get a usable signal level. more than that it dies into the static. cranking the power turns up the near field some but does very little to propagate the signal down the line much further. propagation down that wire depends on how the topography of the electrical grid is laid out. so long as you are within the radiation limits of 221 from any point along that propagated piece of wire (or building where signal is injected) you are legal.
      to further expand on the above RFB has a little series posted here on part 15 carrier current and how to do it.
      http://krocksradioone.com/forum/index.php/board,7.0.html
      best explanation of carrier current you will get.
    - November 10, 2012 at 5:18 pm #29130
      
      RFB
      Total posts : 0
      “carrier current is near field wired/wireless.”
      Even FCC field agents often forget about that fact, as does many radio dabblers with “years of experience” or professional consultants, to which one would wonder why something so simple of a concept of radio transmission would be so misunderstood by those decades of experienced math manipulators. (haha)
      It reminds me of what my math professor told me. Numbers don’t mean squat until it meshes with reality, and even then the numbers usually run into a variable to which leads to the “uncertainty principle”, or better put…the “I don’t know beyond this point thus here is a set stop gap until someone does”.
      I would take a wild guess and say that the reason for the confusion between a CC system and regular monopole center located radiator producing far field is that those who confuse think the power wiring is a monopole, or will radiate like a monopole. Well it won’t, and that has been established long ago by ham’s doing CC during WWII, and even long before that when the early telephone companies were using CC to transmit internal communications and control signals to switch stations located in the middle of nowhere.
      Another thing some confuse is that just because the TX is running at so many watts, that instantly the operator is violating the rules and the signal is getting out too far, though they ignore that it gets out far DOWN the line, and not FROM the line. Big difference between those two points and something that EVERY radio engineer should already have a good grasp of after elementary radio 101 class..dabbling with crystal radios and wires strung everywhere.
      What I have learned about CC comes from information obtained from very old ARRL publications, notes and small articles scattered in libraries (back when information was abundant in libraries), and most of it from actual doing and observation and measuring. Such information, in other fields, would be considered extremely valuable. Some people have a natural knack, or given gift like I do to figure stuff out in their head on the fly without the need of simulators. However here in radio such information seems to be ignored and revert back to the far field concepts, to which that far field concept does not apply at all, and never can. The nature of the utility grid, and it’s incredibly low impedance that swings with a ratio that would make ANY monopole system come crashing down and decades of experienced engineers scratch their behinds wondering what the heck, is the reason why CC is NOT measured or set up like a typical monopole far field radiated signal. It never will be, never can be and no matter how much you mush and slush the numbers, a CC system will NEVER produce any far field like that of a monopole system, regardless of input power applied to the coupler.
      By the time the coupler matches, isolates and maintains proper loading to the TX, your ERP off that power wire is less than 1/4 watt when driven by 30 watts from the TX. You would need several hundred watts just to get a mile OFF the power wire with far field..oh and in the HORIZONTAL polarization to boot. I don’t see any vertical utility wires running anywhere.
      There is a source of information besides what little there is on the web. And that is by doing and observing and measuring.
      Sort of like what Bruce is doing! Wow! Isn’t experimentation and discovery great?!! :p
      RFB
    - November 10, 2012 at 6:11 pm #29131
      
      Carl Blare
      Total posts : 0
      The assortment of measuring tools I have been lucky to accumulate have given me the best feel I’ve had in this CC experience, and I’ll list a few observations.
      The automobile radio is very revealing when listening to a silent carrier.
      In the driveway the silent carrier is so quiet I had to double check to make sure the radio was turned on. My first test was at a mere 1/4Watt which provides a strong near-field signal from house to pole, but after that the signal declines in downward steps, pole by pole.
      Driving on the other side of the street going in the opposite direction the car signal already has sputtering, indicating being on the outskirts of the near field.
      Driving past about the 3rd or 4th pole down the line the sputtering begins to rise abruptly and in a very short distance beyond that the signal is gone.
      Trying the same thing at 1-Watt the indoor near-field measured higher, but the outside silent-carrier test was only very slightly improved at the same distances.
      Testing is as much fun as programming, so I think I will view radio programs as “test audio”.
    - November 10, 2012 at 9:56 pm #29132
      
      Carl Blare
      Total posts : 0
      Way back in 1990 a radio station ditched their Volumax 4300 and I dragged it home, not needing it at the time, since it is designed to modulate an AM transmitter and back then I was running a recording studio.
      Now, out it comes. And I just printed all 33 pages of the manual, which I found online somewhere in 2005 and have saved ever since.
      It’s a “peak controller”.
      Once the Volumax is in the audio chain for the carrier current station, an Aphex Compellor will be added and tested, hopefully the combination will provide a wonderful gob of sound.
      Previously, somewhere in this thread, RFB approved of the idea of this particular audio chain arrangement.
      It sometimes takes me a long time to do what I say I’m going to do.
      I’ve been meaning to say that for five years.
    - November 11, 2012 at 12:13 am #29133
      
      MICRO1700
      Total posts : 0
      Last night I went to check my
      modulation. Lacking a scope at the
      moment (it’s lent out) I decided to
      try a fun experiment.
      I think people have done this before.
      But I’ll mention it anyway. When 1020
      CC is running, all the
      radios in the house are distorted –
      so it’s hard to check modulation.
      I took my Grundig S-350 out in the back
      yard and retransmitted the received audio
      back into the house on 88.3 MHz. It was
      night, and the S-350 was about 50 feet out
      from the house. The signal was not very
      strong – in fact other stations on the
      channel were there, too. I listened in the
      house on 88.3 and adjusted the audio chain
      accordingly.
      This was a big help. The W 60 HZ set-up sounds
      really good now.
      Works well.
      Bruce, W 60 HZ
    - November 11, 2012 at 12:55 am #29134
      
      Carl Blare
      Total posts : 0
      Tha Dood in Poca West Virginia, a part 15 man, revealed a clever trick for setting the modulation level for a part 15 station.
      He says plug the audio output of an AM radio to the input of a tape deck with VU meters, tune first to a high wattage station and set the input level of the tape deck so the meter peaks at 100%, then tune the AM radio to your station and set the audio level into your transmitter so it matches the level of the big station.
      Brilliant idea.
    - November 11, 2012 at 7:33 am #29137
      
      MICRO1700
      Total posts : 0
      Carl – that modulation monitor trick
      is good. I’ve done that before, and
      I will probably be doing it again.
      Soon.
      Bruce, W 60 HZ
    - November 11, 2012 at 7:52 pm #29144
      
      RFB
      Total posts : 0
      “plug the audio output of an AM radio to the input of a tape deck with VU meters, tune first to a high wattage station and set the input level of the tape deck so the meter peaks at 100%, then tune the AM radio to your station and set the audio level into your transmitter so it matches the level of the big station.”
      Unfortunately if the AM radio has AGC..which most do, then that AGC is going to muck with the reading on those meters. What is needed for that kind of measuring is a radio with switchable AGC, or one with the AGC disabled.
      Using a strong station as a reference will bump the AGC downward, and the indication on the meters will be representing what the AGC circuit is doing to the demodulated signal, same with tuning to your station in it’s close proximity to the radio being used to drive the tape deck meters.
      RFB
    - November 11, 2012 at 8:12 pm #29147
      
      Rich
      Total posts : 0
      The AGC function of an AM broadcast receiver usually keeps the average r-f carrier voltage ~constant at the AM detector input when stations of different signal strengths are tuned in.
      So that would keep the maximum audio output more or less constant for different stations, which is what the VU meters on an audio tape deck would display.
      That would give an approximate, relative indication of modulation — which for most commercial AM broadcast stations rarely is less then +/-98%, or even -98/+125% (except for dead air).
    - November 11, 2012 at 9:27 pm #29148
      
      Carl Blare
      Total posts : 0
      rich has reassured us that it WILL work and will keep us legal.
      Green light.
    - November 11, 2012 at 11:48 pm #29152
      
      RFB
      Total posts : 0
      Yeah it will work, but it won’t work accurately.
      I’m sure Rich knows why the modulation monitors used by licensed broadcasters for AM do not measure the modulation with an active AGC at the detector.
      Good thing the FCC doesn’t hold Part 15 AM to the strict specifications like that of licensed AM eh?! Let’s hope another doesn’t either. And the engineers over at VE are trying to figure out how I can make AM C-QUAM deliver 40hz-18khz audio response. Perhaps it has something to do with precise monitor and measuring? :p
      RFB
    - November 12, 2012 at 5:36 pm #29166
      
      Rich
      Total posts : 0
      See http://www.belar.com/AM/rfa2.htm
    - November 12, 2012 at 8:17 pm #29169
      
      RFB
      Total posts : 0
      Probably why so many AM sites are generating all that splatter across the band.
      Kinda hard to determine what’s actually going out when you got a monitor compensating for what’s coming in. Duh.
      RFB
    - November 13, 2012 at 1:12 am #29176
      
      Rich
      Total posts : 0
      Kinda hard to determine what’s actually going out when you got a monitor compensating for what’s coming in.
      It doesn’t.
      The action of the AGC in the linked device affects the amplitudes of the AM sidebands essentially to the same extent that it affects the carrier.
      Such performance does NOT change the percentage of modulation of / in the AM waveform demodulated by an AM detector.
    - November 13, 2012 at 1:17 am #29179
      
      RFB
      Total posts : 0
      Well regardless of what one or two does it, I perform modulation measurements the old fashioned way…the more accurate way and use measuring equipment that doesn’t compensate or alter what I am attempting to measure.
      Again perhaps is why the band is so splattered with garbage eh…because they are not seeing what is actually going out using a piece of gear that alters that incoming signal and what is riding on it sitting next to the transmitter. Why would you need AGC to compensate for signal degradation or anything else for that matter when your inside the same building as the TX?
      I’ll stick to the tried and true method. Always have, always will. FCC doesn’t mind that either.
      RFB
    - November 14, 2012 at 9:18 pm #29199
      
      MICRO1700
      Total posts : 0
      I won’t have time to install it
      until next week.
      That tuning coil is a little shakey,
      I hope it tunes down there.
      This is another interim channel. It’s
      better than 1020.
      I want to see how different things are
      at the low end of the band. Performance
      wise.
      620 Khz, the ultimate destination, will
      happen if I can build an RF generator and
      hook it into that 6AL11 RF stage.
      So 620 is a ways off.
      Bruce, W 60 HZ
    - November 14, 2012 at 10:18 pm #29200
      
      RFB
      Total posts : 0
      I am going to take a wild guess that it’s not the crystal that will take a week to slide into it’s socket, but the tuning of that LC tank.
      Wasn’t that 6A TX on a lower frequency to begin with anyway? If it was it should tune up just fine to 550 or 620.
      RFB
November 15, 2012 at 12:23 am #29201

MICRO1700
Total posts : 0
The transmitter was originally on
640. Then it was on 860. 860 was
a bad channel. 640 has been useless
for decades. I also had an oddball
crystal for 945 kHz, which was lost,
but I did try transmitting there
30 years ago.
Various friends of mine have had the
transmitter. It was in California
a few years ago, and after that, it
was being worked on in New Jersey,
as I’m sure you remember. I’ve owned
it for more than 30 years. I never
imagined it would become the main transmitter
at this Part 15 station.
I’m worried about the adjustable tuning
coil. My friend in New Jersey said it
looked like part of it is broken. I
can’t tell where by looking at it.
But, anyway, this is why I’m not sure
if the unit will go down to 550 kHz.
If the coil has a problem it might not.
We’ll see. If that doesn’t work, or
if the crystal is bad, I’ll just stay
on 1020 for now.
The transmitter is in a physical position
such that it is hard to get to. That’s
why I can’t get it down to 550 kHz right
away. I have to move a bunch of other
gear to even get to it.
Since the Dog Radio studio was dismantled,
I have just had stacks of equipment that
I have been using and working on. Where
ever we end up, there will be a studio
of some kind.
Best Wishes,
Bruce, W 60 HZ
November 18, 2012 at 3:03 am #29230

MICRO1700
Total posts : 0
…but there are interesting problems.
I will be back with a report as
soon as I can.
It’s just on a dummy load right now.
Bruce, W 60 HZ and X-13
- November 18, 2012 at 3:14 am #29232
  
  Carl Blare
  Total posts : 0
  We all have days when we feel like a dummy load.
  550 is a great channel. We have a 5kW station here on 550 that was founded by the St. Louis Post Dispatch in the 1920s, and back then shared their frequency with a Lutheran Church station.
  Stations at that low end of the dial seem to have fatter signals than on the upper end, where signals seem very narrow.
  I am very curious about your 550 report when it arrives.
  - November 18, 2012 at 5:08 am #29233
    
    MICRO1700
    Total posts : 0
    Yup. 550s connected to the AC line
    now. Night is not a great time
    to check telephone poles.
    I’ll be up early in the morning
    trying to look discrete out there.
    There is a wonderful station in
    Vermont that has great historical
    value, and they are on 550 kHz. It’s
    a real down hometown station called
    WDEV. They even have a WDEV truck
    from the 1930s that has been restored.
    I have read about them in the broadcast
    blogs, and you should check out their
    website, just to see that truck.
    They used to stream SOME shows. I don’t
    know if they still do. I have
    tried with the best phased antenna system
    I could build to try to hear them on 550.
    I have actually gotten them a few times,
    but they are not dominant on the channel.
    For years, on Saturday Mornings, they had
    a great show called, “Music To Go To The
    Dump By.” That show is no longer on, but
    it was very popular. The GM ran it, I
    believe, and he did it with his dog, who
    he called, “Butch, the Wonder Dog,” if
    I remember correctly. He would talk to the
    dog and do the show. Somewhere along the
    line, the dog passed on, and the GM retired
    the show. WDEV is one of a kind. Although,
    the station here in CT on 1150 that I have
    mentioned – does a very very good job, too.
    But I don’t think they had some of the humor
    that WDEV had in that “Dump” show. I wish 1150
    was on FM here. That would be great.
    I will have notes probably tomorrow about my
    550 venture. As it seems, my LPB RC-6A CC
    transmitter was just barely on 1020, but
    resonance was good, and the neon light indicator
    that shows transmitter resonance glowed brightly.
    Now, on 550, I am way on the other end of the
    tuning range. As mentioned before, i think
    this particular RC-6A goes from 540 to 1000.
    That’s why I was so lucky to get it working
    so well on 1020.
    Now, that it’s down on 550, it sounds OK, but
    not quite as good as it did on 1020. I can
    only get 4 watts out, instead of 6. The neon
    bulb is dark, so the transmitter is not as
    happy as it was before. We’ll see.
    This is a great experiment as far as I’m concerned.
    More to report tomorrow.
    Best Wishes,
    Bruce, “What are the callsigns I’m using this week…?”
    “uhhh…” “…can’t remember…”
    - November 18, 2012 at 12:10 pm #29234
      
      MICRO1700
      Total posts : 0
      BIG QUESTION
      So far, I cannot get the transmitter
      to go into resonance. It is doing
      only 4 watts out. I have found that
      the right compression trimmer has a
      slight problem. I saw the power jump
      up to 6 watts once, as I was tuning the
      cap, but I couldn’t get it to stay there.
      I had this problem on 1020, also, but
      eventually, it straightened out.
      Will this slight detuned condition hurt
      the 6AL11 RF tube?
      What do you guys think?
      Bruce, W 60 HZ, now on 550 kHz CC
    - November 18, 2012 at 12:27 pm #29235
      
      RFB
      Total posts : 0
      “Will this slight detuned condition hurt the 6AL11 RF tube?”
      Probably not. However it is probably why the audio is a bit low compared to the previous frequency when the LC tank was at closer resonance.
      It’s never good to run a TX even slightly off tune. 2 watts off resonance might not sound drastic on the outside but inside that second half of that tube there is high VSWR because the LC isn’t quite resonating properly.
      Wish I could find my manual to that unit. It was so long ago when I owned a RC-6A. But it sounds like those compression caps are in dire need of replacement.
      RFB
    - November 18, 2012 at 12:52 pm #29236
      
      MICRO1700
      Total posts : 0
      Well, those compression caps
      are old. I don’t even know
      if I’m staying on 550. But
      I want to see how the signal
      goes through the power line
      and get some insight on that.
      I am very interested in what
      the low end of the band can
      do under these conditions.
      I may go back up to 1020 soon.
      Well see.
      Here’s another question for you.
      This 550 rock is teeny. It’s
      not much bigger than a CB channel
      crystal that would go into a
      CB walkie talkie. It has wire
      leads. Although it seems to be
      doing fine and is not physically
      warm or hot on the outside, I
      know that these little crystals
      can shatter just because of the
      energy that is going through them.
      So far so good, but what do you
      think about that?
      Bruce, 550 kHz CC Experimental,
      and tagging along behind – X-13
      on 13.560 MHz
    - November 18, 2012 at 1:23 pm #29237
      
      MICRO1700
      Total posts : 0
      I know you wish you could find
      an RC-6A manual around and that’s
      really a nice gesture.
      But that’s OK.
      You know what’s funny – somewhere
      around here, I have a schematic
      of an LPB RC-5A. I’ve never heard
      of it. It uses only 2 6AL11s,
      instead of the 3 that the RC-6A
      uses.
      I should find it and look at it
      just for fun.
      Bruce, CC 550
    - November 18, 2012 at 2:31 pm #29239
      
      kc8gpd
      Total posts : 0
      speaking of manuals i am accepting pdf’s, or jpg’s scans of any manuals, schematics and tech info related to part 15 and/or carrier current. i have had some server space (about 2gb) donated and i will be building a technical archive for part 15 us. looking for manuals for transmitters, studios gear, processors, etc.
    - November 18, 2012 at 2:43 pm #29240
      
      Carl Blare
      Total posts : 0
      Great kc8gpd
      When you have a link let us know.
      I will link it from my website.
    - November 18, 2012 at 2:54 pm #29241
      
      kc8gpd
      Total posts : 0
      it will be linked to here as a book page
    - November 18, 2012 at 7:56 pm #29243
      
      RFB
      Total posts : 0
      “I have a schematic of an LPB RC-5A. I’ve never heard of it. It uses only 2 6AL11s, instead of the 3 that the RC-6A uses.
      By all means reference that 5A schematic!!! Same puppy for the oscillator/modulator/final. It should have the same variable compression caps.
      RFB
November 18, 2012 at 7:27 pm #29242

MICRO1700
Total posts : 0
Hi Carl and Robert and the rest
of the gang:
Hmmmmm.
My 550 kHz CC signal
goes nowhere.
I will be doing some
exploring. Perhaps
something is broken
and I don’t know it.
It could be something
in my homemade coupler.
Best Wishes,
Bruce 550 kHz zilch radio so far
- November 18, 2012 at 7:57 pm #29244
  
  RFB
  Total posts : 0
  “My 550 kHz CC signal goes nowhere. It could be something
  in my homemade coupler.”
  Most likely it is the coupler. Increase windings..both sides.
  RFB
  - November 18, 2012 at 10:00 pm #29245
    
    MICRO1700
    Total posts : 0
    I will try it!
    I’ll also try to find that
    RC-5A schematic. I know that
    I have it. It’s just a matter
    of going through a bunch of
    stuff.
    Bruce, W 60 HZ
    - November 20, 2012 at 7:02 am #29269
      
      MICRO1700
      Total posts : 0
      WE WON’T GET FOOLED AGAIN
      Even though the tuning circuits
      of my LPB RC-6A are very touchy,
      my inability to get on 550 or
      970 kHz was not caused by that,
      as far as I can tell.
      On 970 and 550, as I tried to
      tune the rocks up on the RC-6A, I
      occasionally heard some squealing
      noises. I began to wonder about
      crystal stability, activity and
      the effect it would have on the
      6AL11 oscillator’s ability to
      drive the final RF amp.
      My brain said, “Brain, get that
      1020 rock back in again and try
      it.” So now, the 1020 rock is
      back in the transmitter. The
      1020 crystal is in a big holder. It’s at least an
      FT-243, but I think it’s larger.
      I’ll have to look that up. The
      970 and 550 rocks are smaller.
      So I put 1020 back in, (not with
      my brain, but mostly with my
      arms, hands, and fingers.) The LC
      was tuned up
      and BINGO!, the resonance light
      came back on and I got 5 watts
      instead of… one. As of late,
      one watt was the best I could
      do on 970 and 550.
      Well, I’m happy. The old LC
      net isn’t badly damaged, as I had
      feared. It’s not great, but
      the problem is those two
      “low activity crystals.”
      So my CC is back on 1020 for
      now, and all is well. And the
      neon light is on!
      The ultimate 620 kHz channel
      will have to be done by external
      RF generating circuitry going
      into the 6AL11 RF osc. side.
      And eventually, it will be.
      But for now… 1020 kHz,
      which is fine.
      We won’t get fooled again.
      Bruce, W 60 HZ and X-13
    - September 10, 2013 at 11:33 pm #32869
      
      Carl Blare
      Total posts : 0
      Wow, this CC Journal ran for about 1-year and has been silent for awhile, but look at all the entries!
      Something new happened and the CC Journal needs to be told.
      My one and only CC transmitter is an LPB 2-20 TX, which was carefully checked out and put into service where it has run as a neutral injection experimental carrier current station until today, when it stopped working.
      Last Friday it was turned on at 9 AM and run 24-hours a day all weekend with a scheduled shut-down last night, but I fell asleep and left all my carriers on all night.
      This morning I tuned to the CC frequency, and there was no carrier! So I thought, “At your age maybe you went downstairs and turned it off after all.”
      But no. I went down and found a cool transmitter that would not turn on. I removed the two fuses, F1 and F2 and brought them up for checking. They are both good! Now I know two parts that are not at fault.
      These LPB transmitters still show up on ebay, but they are getting very old and no longer worth the high prices they have been getting. I bid on them, but others are willing to invest larger amounts and ebay sends me a “sorry you did not win” email.
      The only new CC transmitter is made by Radio Systems and costs big time money, not the kind of budget Part 15 stations tend to have.
      Sure, we’ll sit here and tinker with this relic, it might even work again. But CC could very well become a past experience.
September 10, 2013 at 11:55 pm #32870

MICRO1700
Total posts : 0
Really sorry to hear about that.
Bruce, DOGRADIO
- September 11, 2013 at 2:32 am #32871
  
  MICRO1700
  Total posts : 0
  I have really enjoyed the CC experimentation.
  Like nothing I have ever done before.
  One goofy thing: After a lot of figuring, I realized
  that 620 kHz was the very best AM BCB channel.
  I could never find a suitable crystal. Then about
  a month or two ago, a 620 crystal appeared on E-Bay.
  I missed it. I never saw it – didn’t know it was there.
  Bummer.
  Bruce, DOGRADIO
  - September 11, 2013 at 3:00 am #32872
    
    Carl Blare
    Total posts : 0
    Dear Mister Bruce Dog Radio…
    What you must do is visualize a world of tomorrow in which another 620 kHz crystal appears. Be watching for it.
    You are the best person here at Part15.us. All the rest of us are just lucky to be here.
  - September 11, 2013 at 3:01 am #32873
    
    MICRO1700
    Total posts : 0
    Before the 620 kHz “almost got it,”
    experience, I had been on 1020 kHz.
    Not the greatest channel, but empty
    during the day. The other thing was,
    my transmitter was only made for the
    low end of the AM band. I just barely
    got it to work on 1020: by “stretching”
    the tuned circuits to go there.
    .
    Some of you have heard this before,
    but some might not have.
    I was only running 600 mW into
    the AC line. I used a 10 dB attenuator
    to help the AC line “matching circuit”
    operate in a working fashion. This
    isolated the 6 watt 50 ohm output
    of the transmitter, and made a match
    possible, which successfully transferred
    the RF into the AC neutral. I did work.
    16 houses down the street, I could hear
    my transmission inside a friend’s house.
    But only on one side of the livingroom
    where the AC line entered the house.
    (It was a battery powered radio, a Grundig
    S-350 (not the 350 DL.) A good signal,
    but yeah – with a sensitive receiver.
    I don’t think my circuit was the
    greatest thing in the world – but it worked
    to some degree – and the signal did stay
    inside the AC line.
    So I guess what I’m saying is: a Part 15
    100 mW transmitter could be used for
    CC – IF one knew how to match it correctly.
    My 600 mW into the neutral worked sort of –
    with a questionable matching scheme. 100 mW
    might go a pretty good distance into a good
    matching network for CC. But I think most
    CC matching networks want to see 50 ohms.
    And most 100 mW Part 15 AM transmitters
    want to see a different impedance.
    Bruce, DOGRADIO
September 11, 2013 at 10:49 am #32878

MICRO1700
Total posts : 0
Nice to hear from you!
I missed your note. We must
have put our last entires in at about
the same time.
I love the way you word things.
Bruce, DOGRADIO
- September 11, 2013 at 5:27 pm #32879
  
  Carl Blare
  Total posts : 0
  This is not a boat anchor, it’s a “dead in the water” LPB2-20 TX carrier current transmitter. So far we only know 3 things:
  1.) it doesn’t generate a signal;
  2.) the LED power light doesn’t light;
  3.) the two fuses, F1 & F2 are both good.
  Let’s add a 4th thing:
  4.) it worked for a whole year without any problems.
  Without having so far done any meter measurements I’m looking at the schematic and wondering, “What could shut down the whole transmitter without blowing a fuse?”
  The mystery is actually fun. Yes, the Part 15 way is the best way to live.
  What should I check next?
  - September 11, 2013 at 5:59 pm #32881
    
    wdcx
    Total posts : 0
    No power to the unit?
    - September 11, 2013 at 6:07 pm #32882
      
      Carl Blare
      Total posts : 0
      The two devices in the carrier current rack are the transmitter itself and a Technics FM tuner, which delivers the audio signal.
      The devices plug into a three-way industrial size AC source consisting of a 2-foot extension cord with its own switch and indicator light. The light shows AC presence, and the Technics tuner powers on and off, suggesting the power source is good.
      But the final check of the socket serving the LPB needs to be verified.
      Thank you. I’ll go do it now.
    - September 11, 2013 at 7:48 pm #32884
      
      Carl Blare
      Total posts : 0
      Wondering why DL, the light-emitting-diode power light wasn’t lighting, we noted that the light’s voltage is delivered by D3, 1N4007, which has scorch marks on the circuit board at both of its leads.
      D3 also supplies 15VDC to the exciter board, and if it blew out, there could be a problem on the exciter board.
      The scorch marks might have a historic explanation not related to this problem, but it’s something to check.
    - September 12, 2013 at 2:09 pm #32890
      
      Carl Blare
      Total posts : 0
      After thinking about it for several days, so as to avoid physical labor, we have a PLAN A to get this CC transmitter back on the air. Or back on the wire, as it were.
      YES we suspect D3 as having poofed and believe that maybe two electrolytics on the power supply board should be replaced.
      Experience tells us that after 23-years, electrolytics often go bad, sometimes shorting out.
      Of course once these parts are removed from the depths of the transmitter enclosure they can be checked with capacitor checker and whatnot, but we can’t develop a PLAN B until trying PLAN A.
      If we had some holy water we could just dunk it, but we used it all up curing ailments.
    - September 17, 2013 at 5:49 pm #32949
      
      Carl Blare
      Total posts : 0
      The only carrier current transmitter on hand is down for repair, and I’m thinking about finding a backup transmitter so we can stay on the CARRIED CURRENT during these down times.
      The only CC transmitter we know about is the pricey one from Radio Systems, but hey… here’s the question I have been leading up to for the past 10-minutes…
      There are many licensed AM stations that lower power at night to 2-Watts, or 6-Watts, really low.
      What kind of low power transmitters are they using?
September 17, 2013 at 10:59 pm #32952

MICRO1700
Total posts : 0
I’m sorry to hear you are having problems with that
transmitter.
When I was young… (It was more important –
paying more paper, laughin much louder, yeah…)
Er um… I had been told that some AM BCB stations did use
LPB transmitters for low power at night. But since
those transmitters are all getting old – if they are
still doing it – any stations would probably be using
the transmitters from Radio Systems, I guess.
I’m pretty sure we had a 1000 watt daytimer that was
2.5 watts presunrise authorization. Years ago. Using
an LPB rig was easier than rigging up some resistors
hanging off of a tap from a big resistive load, or
whatever it is that they did (or do now.)
Trivia dept: As far as I can tell, there are 3 AM BCB stations
in the U.S. that run 1 watt power at night. I wonder
what THEY do?
I had that list somewhere…
Gee Carl, I hope you can figure it out.
Bruce, DOGRADIO
- September 17, 2013 at 11:59 pm #32954
  
  MICRO1700
  Total posts : 0
  WDGR on 1210 kHz in Georgia was
  1 watt and about 20 kW day, I think.
  Actually, all I remember is the night
  power being 1 watt.
  This station has gone dark.
  (I might have posted this before.)
  Hey, Carl, maybe you can pick up
  their transmitter!
  Bruce, DOGRADIO
  - September 18, 2013 at 12:09 am #32955
    
    MICRO1700
    Total posts : 0
    1 watt night – 1000 day – 500 critical hours.
    Bruce, DOGRADIO
    - September 18, 2013 at 12:23 am #32956
      
      Carl Blare
      Total posts : 0
      In Carl’s peculiar mind the 1 Watt at night would be a lot more fun than the 20kW day.
      I will try to track somebody down to grab that LP transmitter.
      Full credit goes to Bruce, DOGRADIO.
      EDIT FUNCTION ENABLED CARL HAS MORE TO ADD:
      I went to radio-locator(dot) and learned a bunch of stuff.
      Yes, the station had a CP to add nighttime service to a previously daytime license, at 1 Full Watt.
      Station status: not currently on the air, like Bruce said.
      The owner is Hye Cha Kim.
      Original city of license is Dahlonega, Georgia, but the CP would make the new city of license Lawrenceville, Georgia.
      What I might do, unless I don’t, is contact him and ask about his plans.
      If you could do that for me it would help a great deal.
      The station’s phone number is 706-864-4477.
    - September 18, 2013 at 1:02 am #32958
      
      MICRO1700
      Total posts : 0
      Here’s another oddity:
      WNZK, Detroit
      690 kHz – 680 kHz night!
      The last station of it’s kind in the U.S.
      (I heard there used to be a Canadian AM
      station that went from 710 to 730 night –
      or maybe it was the other way “round.)
      Anyway, this WNZK is 2500 watts day and
      night, 6 towers.
      Bruce, DOGRADIO
    - September 21, 2013 at 1:22 am #33013
      
      Carl Blare
      Total posts : 0
      I love those oddities, Bruce, let us know every one you find.
      In the early days here in Louis, Missouri (he’s been de-canonized), some early stations shared frequencies.
      The Post Dispatch had a station and the Lutheran Church had a station, and at a certain time every day they took turns using the same frequency.
      HEY, at the end of the week the LPB carrier current transmitter is still over on the table waiting for me to take it apart and order parts, but I find plenty of reasons to avoid doing it.
      This week two other Carrier Current threads opened up, with some very interesting discussion, which leads to me now having this book open and a new project in mind.
      The book is The Encyclopedia of Electronic Circuits, and it has several schematics for long wave carrier current devices to use for various purposes. Reminds me of our other unfinished project, the Deep Voice Long Wave 1-Watter being designed by the committee that made the shortwave Big Talker. What about making the Deep Voice capable of operating in a carrier current mode down on 170kHz?
      Spend the weekend thinking about it and let me know next week.
    - September 21, 2013 at 5:01 am #33016
      
      Carl Blare
      Total posts : 0
      In thinking about finding a back-up carrier current transmitter I figured that the transmitter sold by ISS (Information Station Specialists), the T.I.S. company, would be suitable for CC, so I looked it up.
      It is none other than the TR6000, same transmitter as Radio Systems, same uber price.
      Say goodnight, Carl.
    - February 4, 2015 at 10:02 pm #38866
      
      Carl Blare
      Total posts : 0
      This is one long thread!
      Life was good for awhile with the carrier current system built during this thread, but the LPB2-20 Transmitter broke and has been awaiting repair.
      An LPB AM5 has been acquired but needs to have a new output section built for the mid-band, where AM 970 is our frequency of choice.
      Meanwhile, AM 590 is open right now, as the licensed station on that channel has turned itself off for lack of revenue, and it may not be desirable for a buyer because the towers are 40-miles from the city in a farm field only 1kW aimed directionally toward St. Louis. Big expense, flimsy signal.
      590 was the carrier current channel for St. Louis University in the 50s.
      Now it could be mine, but these LPB transmitters, besides being old and prone to breakdown, need to be especially rebuilt for low, mid or high-band AM operation.
      What I need is a new transmitter capable of 590 and 970 operation without major surgery, but the marketplace is dry.
      Radio Systems appears to offer the ONLY carrier current transmitter — at a stunningly high price — and it’s only 10Watts (max).
      Although 5 – 7 Watts is acceptable for 970, back when my LPB was tuned for low band it needed more than 10Watts to feed the wires at 570kHz, where I ran tests.
      Crazy thing is that so many AM stations now have extra-low-power night time authorization, from 1Watt up to 60Watts and such; where the blazes do they get their transmitters?
      I scrolled around and found the major transmitter manufacturers tend not to offer anything lower than 500Watts.
      Only the ALPB can save us in this dark time.
    - February 5, 2015 at 4:17 pm #38868
      
      kc8gpd
      Total posts : 0
      i traded for that greek 0-20w rms 80w pep am medium wave transmitter listed in the classifieds section. you may try looking on ebay for them they are only 600.00 new either plus shipping for free shipping i forget which but it seems to be decent for the price. be sure to specify balanced inputs if you want them though as unbalanced is the stock.
    - February 6, 2015 at 12:49 pm #38877
      
      wdcx
      Total posts : 0
      http://www.eznec.com/Amateur/RMS_Power.pdf
      
      Hope this helps.
    - February 6, 2015 at 7:14 pm #38882
      
      Carl Blare
      Total posts : 0
      Thank you Robert and John…
      I looked on ebay for that Greek transmitter, and it’s not there right now, but it’ll be on again. Maybe that would be a good solution for CC.
      And the guide to RMS Power is worth a weekend of study, I mean, who does understand it… well, there’s you John, certainly Rich and MRAM and Radio8Z, oh and Tim in Bovey… RMS power is everyday stuff for you guys.
      “Root-mean-squared” is daunting for a guy who read Mad Magazine during math class.
    - February 6, 2015 at 9:37 pm #38885
      
      radio8z
      Total posts : 0
      How about the average voltage is 1/(t2-t1) times the integral from t1 to t2 of the voltage dt.
      And the RMS voltage is the square root of (1/(t2-t1) times the integral from t1 to t2 of v^2 dt).
      Math can be your friend.
      Also note that the average voltage of a sine wave over many cycles is ZERO but don’t be fooled into touching the wires.
      Neil
    - February 7, 2015 at 4:30 am #38891
      
      kc8gpd
      Total posts : 0
      @Carl
      here is one. this is what i have….
      http://www.ebay.com/itm/AM-TRANSMITTER-EXCITER-0-20w-Carrier-80w-P-E-P-/251466048131?pt=LH_DefaultDomain_0&hash=item3a8c8b6283
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