Re: Noise in receivers
With most receivers using a diode detector for AM you get a threshold effect so if things work out well, noise tends to get suppressed as it doesn't even begin to turn the diode on. Put in a signal that does get the diode going and the noise appears. Select SSB or CW and turn a BFO on and that will fix the detector threshold effect.
Put some more signal in and the agc starts to confuse things. The dominant stage for noise contribution will go walkies as the signal level climbs and gain adjustments are made in different areas.
Close to carriers, phase noise sidebands will appear and they appear on all signals through reciprocal mixing. Everybody went off hunting mixer and amplifier linearity in the 80's, but phase noise was a worse limitation in the better receivers.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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