Ray, Before you do anything desperate, try the same thing into a dummy load. If it does not happen with the dummy load, you can conclude that it is RF getting into the K2 somehow.
Off-center fed antennas are notorious for creating RF in the shack unless you take drastic steps to suppress it. The proper place to do that is within the antenna system - maybe adding a balun at a point outside the house where the feedline changes from balanced to unbalanced. 73, Don W3FPR On 5/2/2011 5:21 PM, Ray Spreadbury wrote: > Hi Elecrafters > > I have recently bought a second-hand K2 with the KSB2 SSB module, the KPA100 > 100 watt amplifier& the KAT100-1 antenna tuner. Everything appears fine > running either QRP or 90+ watts on all bands except 80 metres. I am using an > off centre fed dipole (133') and the KAT100-1 antenna tuner to match. > > Running in excess of 10 watts or so on 80 metres however when I switch the > microphone, the tuning apparently shifts to another frequency on the band. > The shift may be a few Hz or even a few 100Hz. The receiver is then on that > new frequency. Reducing power back to a QRP level, the transmitter& > receiver behave normally. > > I guess there's something wrong with the 80 metre sections of the KPA100 > and/or the KAT100-1. > > Any clues of what I should check please? > > 73 > > Ray, G3XLG > > > > ______________________________________________________________ > 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 > ______________________________________________________________ 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
