[Elecraft] When do you use fast AGC?

[Ron D'Eau Claire]

I do use "fast AGC" at times but I'm basically a "non-AGC" CW operator
unless I'm just casually tuning around and chewing the rag with stations
with good strength. I don't appreciate listening to band noise that is
greatly amplified above its real level. If a signal is 20 dB above the
background noise, I want to hear it standing out 20 dB above the background
noise. But AGC works hard to make the background noise as loud as the
signal. 

I guess that's a valuable feature in marginal conditions where you're trying
to hear a weaker signal that may send only an element or two after a much
stronger signal finished sending, provided there isn't another signal in the
passband killing the gain as Tom observed. It saves having to "ride" the
gain control manually, but I find AGC extremely irritating under those
conditions - like trying to operate with a loud vacuum cleaner (a "Hoover"
to our friends in England) roaring next to me in the shack as the background
QRM is pulled up to full volume whenever the signal is not present.

So I use either AGC slow for casual operating or no AGC at all and ride the
gain manually, especially if I'm digging for weak signals.

So when do I use "fast" AGC? When I'm listening to a strong AM signal on the
K2 that has significant QSB. The fast-acting AGC follows quick changes in
the carrier level more closely. That's true of PSK or other digital modes in
which there's a steady carrier present as well. 

Ron AC7AC