Frank and all, Well, I have been responsible for a number of posts on adjusting the AGC threshold. I have found that each K2 is a little different, and one of the dependencies on the proper AGC threshold level is the actual voltage out of the 8 volt regulator, but I have not been able to come up with a clear and easy 'formula' to determine the proper AGC Threshold voltage setting - the best way is to 'do it by ear' - that says there are more things than just the 8 volt regulator voltage which affects the proper level.
I will say that the AGC Threshold should be set somewhere between 3.7 and 3.8 volts, or if you have a desire to set it lower, consider 3.65 volts as an absolute minimum. If the Threshold is set too low, the S-meter will become difficult to set and you may not be able to obtain an S-9 indication with a 50 microvolt input (XG1 or XG3 output level). I do recommend evaluating the AGC on/AGC off difference with no antenna, on 40 meters, and with the preamp off - but the choice is yours on those parameters, if you want to adjust it for a different set of conditions, you will obtain different results, but it will still work, there is no real 'right and wrong' set of conditions, it is really a matter of choice (as long as you are willing to accept the performance that results from your choice). The RF Gain control works in the same circuit as the AGC Threshold, so if you have a high noise level, you can always back off on the RF Gain to reduce the threshold temporaily and keep the noise (or a strong signal) from activating the AGC - the consequence is that the S-meter will not read as it was calibrated with the RF Gain reduced, but under extreme conditions, that is a small matter IMHO. 73, Don W3FPR > -----Original Message----- > > Others have said to hook your rig to a dummy load while adjusting > the AGC in > this way. I completed the AGC adjustments when 20M had a very > low noise > level > during the evening hours. Now I have more than enough room > filling vol > without > needing amp spkr's and typically run the audio around the 10 O'clock > position. > Others go to great lengths to say to adjust it with the Pre-amp > off etc .... > > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.16.7/618 - Release Date: 1/6/2007 7:47 PM _______________________________________________ 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
