Quote:
Originally Posted by ChrisW6ATV
Why would the type of sound IF matter with that low-power TV station? Isn't the sound going to be on 87.75 MHz with 25 kHz deviation, 10dB below the video carrier on 83.25 MHz in any case?
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If there's no picture carrier 4.5MHz below that FM station, most analog TV sets won't demodulate it, as there won't be a signal at 4.5MHz at the video detector diode. (I assume that the FM station at 87.7 or 87.9 has no "video" signal associated with it. Though someone could put up an MTV LPTV station on channel 6 so as to become a fake FM radio station).
If you set a TV to channel 6, or cable channel 96 (cable channel using the spectrum between 88 and 108), inject a local oscillator into the TV set antenna port, along with an antenna picking up FM radio stations, and tune that oscillator to a frequency 4.5MHz below a desired FM station, you should hear it out of the TV set's speaker. It will probably sound overdeviated though.
If your town happens to have two FM stations approx 4.5MHz apart, you may hear a really yucky mix of both their audio.