Total posts : 45366
I could not agree more with Neil’s post above.
The adjustment control on the C.Crane, for example, is stashed inside for a reason. Clearly all the people who post on Youtube and write reviews on Amazon and such who talk about cranking this up for better sound quality and coverage are not people who have any clue that they are making their transmitters illegal. Clearly the transmitter I tested was putting out far less than the legal limit (although it did deliver the range promised which was 30 – 75 feet line of sight). Someone with the proper test equipment could indeed adjust this control for maximum legal output. The percentage of people equipped to do so is rather limited. My mission was to see if full legal output coule be obtained and rather than stand in the field turning the knob a titch, remounting the transmitter at height, testing, taking it down and doing it again until I reached full legal limit was clearly too time consuming. But simply turning it up all the way, we know that it can in fact reach the legal limit, and much more. I certainly do not condone using it over the legal limit. My mission entirely was to see if the transmitter was legal as arrived (it was) and what it’s potential may be.
Bottom line to FM’ers is that if you’re getting over 250-300 feet there is simply no way you’re legal. I’ve now tested three certified transmimtters. Two of which had over the limit output as shipped, and even at this higher than legal output they didn’t get to 300 feet in clear path line of sight transmission. And remember, I’m doing this range testing in a very small town in the boonies away from 90% of the noise, interference, and crowded bands in a major city, and I’m testing line of sight — nothing at all between me and the transmitter.
ANY change to the antenna on a certified transmitter makes it illegal. Clipping a 6″ piece of wire to the telescoping antenna cancels it’s certification.
For me personally the concept of FM Part 15 “broadcasting” simply isn’t viable. FM is best used as a way to get audio to various parts of your studios, etc and perhaps for in house or yard casting. I can guarantee you that any FM transmission going 300 feet or more would test way over the legal limit if I were to set up the FIM at 3 meters and test it.
Many are clearly hoping to do what is not possible within the laws.