Topband: 1/8 wave vertical
Tom Rauch
w8ji at contesting.com
Thu Dec 27 16:27:33 EST 2007
> My point was that in an environment where either noise or
> other signals are
> capturing an AGC, the bigger signal, even the one dB
> bigger signal, will
> prevail. That is because a receiver AGC can react to a 1
> dB difference, even if
> the human ear may not.
>
AGC doesn't work that way.
It isn't a volume expander or gated threshold. It is a long
time hold gain control that operates on the total peak power
in the bandwidth of the system up to the point where AGC is
detected. A 1 dB change in a small signal where noise power
dominates still comes out as the same ratio.
Are you are confusing it with FM systems where a signal will
capture? If so, even that doesn't work with only a 1dB
difference.
73 Tom
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