Topband: 1/8 wave vertical

Tom Rauch w8ji at
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 

73 Tom

More information about the Topband mailing list