So my shortwave radio has adjustable AGC constant with settings between 0.1 s to 8 s.
I always find myself using the fastest AGC settings. Often, I experience 20-30 dB fades and if I use the slower AGC settings, what happens is that the station is too weak to be received until the AGC compensates.
On the other hand, I can't seem to figure out why or when would I want to use the slower AGC constant.