Sounds like RF feedback. Do you see the same problem with a dummy load? 73,
Scott K9MA Scott Ellington Madison, Wisconsin USA On Oct 14, 2010, at 2:37 PM, Luigi Casari wrote: > Ragards to all, > I have just discovered a problem, 28 MHz or 21 MHz SSB, during transmission > the power drop down to abt. 10/15W. > > This after few second of transmission, the power staies low for some seconds > and then increases again. No question of microphone, I have tried with MC85 > and Pro set, also change the levels of the mic gain and compressor without > result. > > I have tried on other frequencies and have not been able to recreate the > problem, only in 21 and 28 MHz. > Don't believe is a problem of SWR and some protection what limits the power, > the antenna is the same from the 10m to the 40m, Opti Beam, and the SWR > where have done the tests are low. Also the internal SWR meter of the K3 > give me low SWR. > Even in 160m, 80m or 6m with others antennas no problem. > > In FM mode I don't notice any decrease of power, 110W constant. > > Some idea? > > 73, Luigi HB9CXZ > > hb9...@ticino.com > http://web.ticino.com/hb9cxz/ > > ______________________________________________________________ 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
