Wow, Don, the effect of setting the AGC THR is dramatic! I live in a very rural location that seems relatively free of man-made noise. With antenna connected, the K3 S-meter shows about S-5 background noise. (S-0 with no antenna!)
Surprising to me, turning *down* the AGC THR to 002 (was set to 008) really quieted things down and made signals "pop" out of the noise the way you describe. (Note: NF and NB are OFF) I could hear the background noise level rise monotonically as I increased the THR setting and fall as I decreased it. With seven AGC variables to adjust -- DCY, HLD, PLS, SLP, THR, -F and -S -- setting AGC up for a given operating scenario in a given location seems like a very complex topic. Is there any way this could be reduced to a tutorial for the K3 Wiki (like K3NA's entry at http://www.zerobeat.net/mediawiki/index.php/K3_Receiver_Gain_Configurations, which addresses the "no AGC" case)? This might create a run on N-GENs... -- 73 -- Brian -- K1LI On Tue, Feb 2, 2010 at 4:50 PM, Don Wilhelm <[email protected]> wrote: > I just thought of something that might help those confused by the AGC > Threshold setting. One other way to look at the required AGC Threshold level > is to think of it as an S-meter level If your noise is S-1 or lower (on the > K3's S-meter), you can set the Threshold to 002 or higher and all may be > well OTOH, if you have an S-7 noise level indicated, the AGC Threshold > should be set to 008 or higher. > > This is not an exact science number - the AGC Threshold menu parameter > values are not tied to the S-meter, but hopefully the relative scale can > give you an indication of which way to move the setting to avoid activating > the AGC on the ambient noise coming in on your feedline. > > As I have said before I believe the default setting of 005 is even too low > - mine normally is set at 008 even though I have a relatively quiet > location. > > 73, > Don W3FPR > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
