Oops, mistakenly sent this with the wrong subject line. Jack's measurements of the K3 AGC on the link listed below are quite interesting. As my noise level on the low bands is usually at least S3 or 4, his plots indicate that the noise (S3 is approx -90 dBm) is either in the linear range of the AGC, or just barely in the software AGC range. Don't we really want the band noise in the flat part of the AGC curve, down near -130 dBm? Would operating with the ATT on and/or the RF gain turned down help move the band noise to this part of the curve, resulting in a higher S/N ratio for signals just above the background noise?
Steve N9SZ Barry N1EU wrote: >Steven.Zabarnick wrote: >> >> I'm somewhat puzzled by the behavior of the AGC THR adjustment with >> respect >> to band noise. My understanding is that the AGC THR setting adjusts the >> level at which the AGC is activated. Thus, I would expect when listening >> to >> band noise (QRN) that if the noise is activating the AGC, using a higher >> number would prevent AGC activation, resulting in a lower background band >> noise. >> >A higher number means that AGC compression begins at a higher signal level, >so a higher number means you'll hear more noise. > >take a look at the graphs at >http://www.cliftonlaboratories.com/elecraft_k3_agc_and_s-meter.htm#AGC_SLP_and_AGC_THR > >73, >Barry N1EU. _______________________________________________ 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
