Describing the background was intended to put the AGC discussion in context and show why AGC and S-meters are so closely integrated. A receiver with an S-meter is just a sensitive, selective RF voltmeter. Without AGC that "voltmeter" has a very limited useful range. That's why S-meters didn't appear until superhetrodyne receivers with AGC came into use.
I turn AGC off a lot because AGC, in the absence of a signal, brings up the background QRN to almost to normal listening volume. So the bands sound noisier than they are. Our ears can follow a huge range of sound levels, but receiver AGC fails to make use of that. It tries to deliver everything to our ears at the same volume. Turn AGC off and set the RF gain so the band noise and any weak signals are very faint, and you'll hear the bands as they really are. If there's a signal down in the "mud" that you want to copy, you can turn up the RF/AF gain to bring it up on volume for easier copy, otherwise you need not have your ears assaulted by artificially-high QRN. Still, I use it a lot too. It's a convenience if I don't mind its effects. It comes in especially handy when contesting, working a net, etc. so one doesn't have to "ride" the gain control by hand. Ron AC7AC -----Original Message----- Lots of good info about AGC, but I'm thinking a lot of it is not that useful today. In the old days, it sounds like you HAD to turn the AGC off for things to work right. That's no longer the case and our operating habits can, and have, changed. In my case, I leave AGC on 100% of the time. I'll turn the RF gain down to increase the signal to noise ratio. Turn the RF gain down to the point where the AGC is not doing much and you have the rig running as if AGC is off, but it is still there, able to respond to a big signal on freq to protect your ears. Can those of you who turn AGC off tell me why? What does it do for you that the AGC doesn't? - Keith N1AS - - K2 5411.ssb.100 - _______________________________________________ _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
