Stu A couple of thoughts.....
You didn't mention if the oscillation was occurring with the amp driving an antenna or a dummy load. The Elecraft transverters have lots of nice features but they are quite poorly shielded. If you were using an antenna you might be getting an RF feedback loop via the various rear-panel connectors which rely on the PC board for grounding rather than the case. Clip on ferrite beads on the cables can help. If you were running the amp into a dummy load then the problem is more likely impedance related as you suggested. When I built my XV222 the manual failed to suggest that the paint be scraped off the case where the output coax connector is attached. If you haven't already done this, it might be worth a try just to ensure proper grounding. 73, Steve VE3SMA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html