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Re: Conductive paint

> >For some unknown reason some amplifiers could demodulate FM! Demodulation 
> >by rectification of AM signals made sense, but FM???

For what it's worth, I noticed this effect at an FM broadcast station
several years ago, and the cause turned out to be "AM noise" on the FM
carrier.  Looking at the signal with a scope, the FM waveform decreased
slightly in amplitude as the modulation moved the carrier frequency away
from center, almost as if it were fed through a bandpass filter that was
just a shade too narrow.  Rectification caused the audio to be heard in
a nearby telephone.

73, de John, KD2BD

-=-=-=-=-=-=-=-=-=-=-=-=- John A. Magliacane, KD2BD -=-=-=-=-=-=-=-=-=-=-=-=-
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