Gerhardt, It sounds like the AGC Threshold is not set properly.
I would proceed by first checking the alignment of the bandpass filters in Transmit mode (at 2 watts) and then set the AGC Threshold for optimum receiver sensitivity - with no antenna connected and AF and RF Gains set to max, adjust for the highest voltage at Control Board U2 pin 5 which yields no change in the audio noise when switching the AGC between OFF and ON. That will usually result in a voltage in the range of 3.65 to 3.8 volts at U2 pin 5. Set the S-meter end points (CAL S Hi and CAL S-Lo) after setting the threshold. If that does not cure the problem, then look for a problem in the IF receive chain - that will be where the signal tracing is required, follow the p[rocedure for receiver signal tracing in the Troubleshooting appendix of the K2 manual. 73, Don W3FPR > -----Original Message----- > > got a K2 from another OM on my workbench. It's got a > receiver problem and I just want to make sure I do the > checks in the correct order and I'm looking for hints, > if available! > > Thanks in advance! > > So here's the problem and what I want to do. It seems > the receiver runs with "handbrake on". So the s-meter > shows 3 bars without an antenna but the rf gain is > fully clockwise. I can reduce signals to zero (using > RF gain) with this K2 which I can't using my own K2. > So mine has a higher sensitivity. > > Any idea what's wrong? > > What I want to do: > - s-meter alignment > - I.F. amplifier alignment > - (maybe band pass alignment) > - signal tracing receiver and synthesizer > > Kind regards > > Gerhard > DH3FAW > _______________________________________________ Elecraft mailing list Post to: [email protected] 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
