>
> It simply means that the time constant holds the peak for
> some time, and the S meter stays up for that fixed period of
> time. It is different from other AGC as they fall off
> linearly with time.
This is correct and to further describe it; Let's assume you tune into a
strong 20db over 9 signal. Your agc voltage is quickly developed across a
diode which in turn reduces the gain of the I.F. amp but not quite quick
enough to prevent an unatural sounding "pop". Then, suddenly, the signal
goes away and the agc voltage remains high thus keeping the I.F. gain at a
low level for a determined time. This is the "hang time". During this time,
you won't be able to hear weak signals. The S-meter also hangs on 20db
during this time. This can be annoying if you are tuning across the band.
It's easy to miss those weak signals due to the long hang time. TenTec
stopped using it with the Paragon/Omni V series.
Of course one way to avoid the hang time is to simply turn off the agc and
ride the I.F. gain control. I'm not sure exactly why they started this hang
stuff unless it was to help reduce the big pop you hear on the first
character of a strong cw station. Once the first pop is over with, the agc
would make the signal weak enough so you heard no more popping until there
was sufficient time for the agc to decay again.
I've had several Corsairs and Hang AGC seemed to be most obvious on that
series. Rag chewing SSB fans don't seem to be as bothered by it as do cw/dx
hounds.
Steve Ellington
Amateur Radio Operator N4LQ
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