It may be that there are two AVC loops. I'd expect one working at RF to
protect the A/D from being overdriven, and a second one working after
detection and filtering to level the audio for the speaker. It may be
that the simple AVC reading option reads only the RF AVC. If so, that
could show a strong signal indication while receiving a weak signal
adjacent to a strong signal, when the strong signal was still in the A/D
input passband. But the combination of the strong RF AVC and weak audio
AVC ideally should be indicated as a weak signal.
73, Jerry, K0CQ
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Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.
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