W1QJ: When I get back to troubleshooting my AL1500 I will print out copies of the many emails sent to you containing the results of all the measurements and tests I conducted on the amp. Those emails documented to a nauseating degree the problem(s) with my amp and will be my guide "the next time around" with the amp. I'm not sure if you actually read all those emails as your replies seemed a little vague. I'm not complaining as I tend to be very "wordy" and if I received emails as detailed as I sent you I'm not sure I would be patient enough to read them carefully. Your several suggestions proved pivotal in the troubleshooting and allowed me to "zero-in" on what I think is the issue with the amp. I thank you for that. Unlike before, I am now "armed" with parts, and have the very heavy amplifier moved to my test bench, where unlike my operating table, I can "get serious" with the amp and rip into it and fix the damn thing. I like things that work. After 50 years of amateur radio, and spending most of my working life "fixing things electrical and electronic" I'm now retired and all I want to do is get-on-the-air and operate. I have little or no patience with very expensive gear that doesn't live up to it's cost. That is why AMERITRON "is on my list" as a manufacturer to be avoided. And.....it would be nice if AMERITRON included AN ACCURATE AND COMPLETE SCHEMATIC with their products, especially the AL1500. What a disappointing outfit AMERITRON is.