I had a look at Jack's video showing the power fluctuations. They are quite rapid and continuous. If they stay like that, it will be a big help in tracking down the problem. The tx signal can be traced through the various stages with an oscilloscope to find where the steady signal begins the fluctuations. In my case, the darn fault would always disappear just when I was ready to start! However there are a few simple tests to do, before taking the covers off.
Turn the power down to 12 watts or less. Do the fluctuations disappear? If so, problem is in the 100watt Amp. If not, 100watt Amp is eliminated. Are the fluctuations present at the transverter output? I have the 2meter transverter installed. So in my case, I only needed to look at the 2 meter output. If fluctuations are here, then the LPA board can be eliminated. There is also a method to look at the tx signal on the P3. It is described in the manual. Are the fluctuations present at this intermediate point? I do understand your frustration, Jack. There was a point when I was about to chuck my K3 in the trash. I'm glad I persevered and now I have a superb radio. 73 Roger, VK4YB ______________________________________________________________ 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