3 when it was all said and done. I knew hem personally. HS Drop-out. Biker. Ham. Created and funded the Ham Station at the Tampa Museum of Science & Industry, operated the best 2 meter repeater in Tampa. Loved by all until he was busted by the FCC. He now has no radio friends but me. He played by the rules but when the FCC told him the rules applied to $$$ he went a differnent path. He had a bigger listenership than some canned broadcasters. He is a legend in Tampa.
Thelegacy wrote in this clip from Reply #13 above: The FCC knows that the common man buyng a transmitter has no way to measure the field strength. So the whole 15:239 rule is MOOT if you can't accurately measure it.
The best assurance of compliance with FCC §15.239 is to buy/install/use an untweaked transmit system already certified as meeting FCC §15.239, in the configuration it was certified.
That means no "clip lead" wires attached to the stock antennas of such systems as shown on the website(s) of some manufacturers, and no use of "secret switches" that may be accessed by the knowledgable.
But this also may mean that a calibrated FI meter shouldn't be needed to assure the Part 15 FM operator of compliant operation (assuming that such is the goal).
First of all, what one rogue FCC agent was quoted as saying does NOT change the law. A sworn statement doesn't make it an accurate statement. It certainly doesn't change the regulations.
Second of all, at NO TIME ANYWHERE are the limits on Part 15 FM operation defined in FEET, distance or COVERAGE. They are simply defined as 250uV/m at 3 meters. Period. In the only test I've done, 200 feet was the best I got with solid reception. But 200 feet, or 500 feet, or a thousand feet, is NOT the rule, is NOT the regulation. Field strength is the ONLY defined limitation in the regulations. See below.
In this post it was stated by the OP that the agent did not know the rules, then we expound it to mean that somehow the rules have now changed. The have not.
The antennas used on the field strength meters used by the FCC (and me for that matter) including the ZTechnology R-506 and R-507 as well as the Potomac FIM-71 are dipole antennas with a balun in the center. Yes, they may appear to be about a meter long. Actually the length they are set at is dependent on the frequency that is being monitored. Also the coax connecting them to the FIM is also figured into the readings to account for losses in the cable. They are very precise instruments and in no way are connected to what a Ghetto Blaster may be capable of. If I recall, the FIM-71 measures down to 10uV, the R-506 if I remember, goes down to 2uV. These are very sensitive and precise and will catch a signal that no radio will ever get.
No the FCC doesn't need to provide the common man with a FIM. Not any more than the Department of Transportation needs to provide with us with crash test equipment to be sure the bumpers on our cars meet federal regulations. You buy a certified transmitter and use it as intended, and you are legal. Anything beyond that you WILL need a FIM to prove that whatever you have concocted is legal, e.g. 250 uV/m at 3 meters.
If every time a law enforcement officer, or federal or state agent of various agencies misquoted a law or made up his own version on the spot, it changed the law or created a valid loophole, the entire system would be a disaster.
So far, based on the one quick test I did, a new certified Decade CM-10 transmitter, in wide open spaces goes just to 200 measured feet into alegedly "good" radios, a Tecsun and a Grundig, and could make it to 250 feet barely with carefully diddling with the antenna direction on the Grundig. And that it didn't reach much further than that into my car radio. What we don't know is the actual field strength of that transmitter. Is it at the legal limit? Or are they in fact made with a substantial "cushion" be insure they're all legal? We shall know more soon.
I'm waiting for the Wholehouse 3.0 to arrive, and then for some time to get out and get setup. I plan on doing my readings with BOTH the Potomac and the ZTechnology units to have double verification of my readings. I will also be attempting to take output readings from the transmitters themselves to see what they're putting out. Another example of a specification that really means nothing. Whether they put out 10 mw, 50 mw, a hundred mw or a watt, doesn't matter if the antenna design is such that it limits the field strength to the legal limit. But I think some actual FI readings and output numbers will give us some idea where these things are at.
Tim in Bovey
What is your take on the FCC busting a person using a certified Talking House AM Transmitter with the wire that came with it no fudge with the ground? And I'd also like to know if anyone was ever Busted using a certified FM transmitter in stock condition? I totally get that the FCC is more pro AM here, but too there has been many legal AM stations or what should have been legal following the ground rules and yet they were busted for running their station. How would someone know if their Talking House AM Transmitter was putting 125 mW. I'm sure the agent should have simply warned that his transmitter was a defective unit and was over the 100mW limit. Now I know that the newer Talking House AM Transmitters are actually 92.5 mW. So I am sure now that the makers of that transmitter was not going to take any more chances with their customers. I know AM and FM are not the same, but if a transmitter is certified and yet you get a NOUO or told to shut down there really needs to be a good reason for this. Id like to find more behind this story as I am sure there could be an interference or foul language issue we may not know about. Its why I am sure to keep it clean on air.
RE: Clip from Reply #19 - ... I know AM and FM are not the same, but if a transmitter is certified and yet you get a NOUO or told to shut down there really needs to be a good reason for this. Id like to find more behind this story as I am sure there could be an interference or foul language issue we may not know about. ...
The use of an unlicensed transmitter FCC-certified under Part 15 does NOT legally shield its operator from FCC actions if that system is installed/used in non-compliance with Part 15.
AFAIK, none of the FCC NOUO citations applying to Part 15 AM/FM infractions has ever referenced interference, or foul language.
But if you know otherwise, please post your proof.
Before we all go too far down this path once again, just a comment to theLegacy that is based on the real world.
If you're using a certified Talking House, there is very little that you can do to make it not compliant with Part 15. Just install it unmolested, as per instructions, i.e., plug it in and start transmitting.
Where you'll potentially get into trouble with even a Talking House is adding more grounding, i.e., grounding the case. The Talking House is certified to use the 3 prong power cube, with grounding at the power outlet.
There is only one case that I know of in which an NOUO was issued for a Talking House, and it's never been made clear exactly why that happened (i.e., no one is talking). With that being the case, you have to assume that they did something out of the ordinary (either mucked about with the internals of the transmitter, or violated the 3 meter rule - there are really no other options).
I don't know otherwise, but for the FCC to come to a person's house who runs a Talking House AM Transmitter again no mods no long ground leads or roach clip attached to the wire to make it longer and nothing other than how the transmitter came out of the box. Now being that one is broadcasting and lets say they are playing Rap and we all know lots of Rap songs are flooded with foul language. Even some Rock songs can be full of it. Someone could have complained about the station due to the content and when the FCC came to check the station out they notice that the transmitter is putting out more than 100mW. Again 25 mW son't exceed that mile range on a wire antenna indoors. Now outside it would most likely carry quite a distance and if the FCC saw your transmitter was overpowered you are in for a NOUO. What promped the FCC's visit? I know nothing was mentioned about interference. Was the operator so grossly overmodulated he was bleeding nearby stations? This could be another thing that could prompt a visit. The FCC monitors the station and can see you have the volume up so high the station sounds like pure T garb. Now it don't matter if your certified or not you overmodulate and you're in to trouble for exceeding 100% modulation. Again I know nothing was mentioned of this but again somthing prompted a visit. There was something that was not normal about the way the station was operating which made the FCC show up. Maybe the operator was using a call sign that some other licensed station was using. There is far more than field strength and power that will get you in trouble with the FCC but they will use that to quickly justify why you are to be shut down. Its easier to say a station was overpowered than to say He or she was overmodulating or played offensive content and the neighbors complained. Kind of funny how no person who was using it for real estate ever got busted.
RE This clip from Reply #21 above: The Talking House is certified to use the 3 prong power cube, with grounding at the power outlet.
Just to note that an effective r-f ground does not exist at any of the terminals of a 3-prong, a-c power cube or outlet.
Whatever r-f ground that is available to such configurations may be provided by the buried ground rod near the a-c service entrance.
But the conductors leading to that ground rod can produce (unrecognized) radiation, which may lead to non-compliance with Part 15.
Rich's guideline of using certified FM transmitters in their verified certified state as a simple solution to being complant with 15.239 works for me, it's exactly what I've done to discover that four different certified FM transmitters put out approximately the same field strength according to a spectrum analyzer at a given distance.
But that didn't solve the maddening problem of multipathing being encountered by ordinary movement in the building, causing interference on all four radios in various rooms.
Experimentation yielded a lucky solution in the form of a mid-fed L antenna connected by clip lead to the folded telescopic antenna of a C.Crane.
Spectrum Analyzer reading with 12" vertical telescopic antenna per certification = 50 dB;
Spectrum Analyzer reading with mid-fed L antenna = 48 dB.
There. No multipath, and a drop of 2 dBu from verified certified field level.
A gentle reminder that Part 15 AM transmitters are rated at input power. The output power is considerably less. More likley micro-watts.
Sroll down: Another Part 15 Troll.
It's a closed group. What did they say?
Dang!
I couldn't get access owing to FB non-membership.
A gentle reminder that Part 15 AM transmitters are rated at input power. The output power is considerably less. More likley micro-watts.
According to measurements made by Neil (Radio8Z) and others, the output power of the final r-f stage of a Part 15 AM transmitter with 100 mW of d-c input power that is available to drive the load connected to the transmitter can range from maybe 35 mW to 85 mW or so, depending on the class of operation and adjustment of that final amplifier.
But much of that power is dissipated in the resistances of the loading coil and r-f ground connection. So the amount of radiated power is much less than the actual output power of the final r-f stage, whatever that is.
I did say "gentle."