Are you using a separate RX antenna ? There is a recognised issue with the KXV3 and insufficient isolation that can give rise to spurious oscillations.
73 Stewart G3RXQ On Sun, 10 Feb 2008 21:43:55 +0100, Björn Mohr wrote: > I had my first weekend with the new K3 and bumped into a strange problem. It > actually took me a while to figure out what was going on. When keying up > with the amplifier in line on 160 I was not able to run more than 400 watts > before the SWR protection in both the amp and SWR meter kicked in, it all > happened in milliseconds as if arcing was going on somewhere. I thought I > had an antenna problem and went through the system without finding anything > strange. After some time I hooked up my MP and all was fine again, running > full power without a problem. That's when it hit me - RF feedback had to be > throwing my K3 off frequency and therefore tripping SWR protection and the > alarm. > > My setup has been working fine with the MP for over a year, never seen a > problem like this. A common mode choke is in line with the TX antenna and > most of the wiring used with the MP was used for the K3 except that power > where fetched from my 12 volt bus. The MP is a field model and gets its > power straight from the mains, same phase as the 12 volt bus. > > I would be interested to hear if anyone else had similar problems and found > a good solution. > > 73 de Björn /SM0MDG > > > _______________________________________________ > 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 _______________________________________________ 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
