Total posts : 45366
On Jan. 18 I added a comment to this thread about Radio Frequency Interference being picked up by the AM25’s 3-meter antenna and back-modulated into the audio. At that time I suggested that frequencies above the AM band could conceivably be encountered owing to the short antenna, and now I have discovered FM 107.7, 100 kw, 4-miles away, is in fact clearly present on my silent carrier.
The Part 15 rules require accepting interference from licensed stations, so the solution needs to be home-made.
1.) move my antenna;
2.) build an FM trap;
3.) live with it.