Guys, this is what AGC is FOR. Older radios that had AVC used it because AGC did not work well. (ANL was just a clipper and a way of dealing with impulse noise in an AM receiver, taking advantage of how clipping the peaks greatly reduced the average power of the noise.)
The trick here is to use the AGC-T opposite the way that Flex suggests that it be used. Most of us prefer the first 10dB or so to be linear so that a 10dB change in signal level translates into a 10dB change in audio level. If you do that and push the noise down, it works almost as well as DSP-based noise reduction (NR) but without the "gargles" and other anomalies (which drive me nuts). The point of AGC is to flatten the level response so that stronger signals do NOT sound different in level. Certainly the AGC in the Flex radios is pretty good. So here is what I suggest: rather than adjusting the AGC-T downward until you get a clear and subjective halving of the noise floor level (about a 10dB cut), I recommend you slowly increase AGC-T until you no longer hear an increase in noise level. You want your AGC threshold set right at the noise floor. This should keep everything, noise and signal, at that level. I don't like this setting because it means that I have to listen to the noise at the same level as the signal between and words (in SSB and depending on AGC speed), but it does mean that you should hear the really weak ones at the same volume level as the really strong ones. -- Brian Lloyd, WB6RQN/J79BPL 3191 Western Dr. Cameron Park, CA 95682 br...@lloyd.com +1.767.617.1365 (Dominica) +1.916.877.5067 (USA) _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
