"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
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
"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
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
That's good to hear the RC-6 is on the bench and being checked for you Bruce! Won't be long now!
RFB
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
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
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 [email protected]
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
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.
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
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.
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.
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.
It's next test will be inside an LPB AM 25 transmitter.
RFB
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.