Thanks all for comments. Many good points, esp testing into dummy load. I rebuilt the PS from the kit about 2-3 years ago; I bought a new pair of matched 3-500Zs from a reliable source about 4-5 years ago when I put the amp back into service after decades on a shelf. I don't see any difference in output over time. I use an MFJ power-up delay switch and feed the amp with a Mark 5 through an MFJ relay box. Takes 75 watts input nominal to get to 200 ma on the grids. Output goes to a Palstar AT-1500DT transmatch, which also has the RF power out and SWR meter. Everything goes through a Balun Designs 1:1 choke unun, 5KW capacity, into the antenna switch to wires and verticals. I see minor differences (about 10w max) in required drive o different bands. My plan is to borrow a dummy load and test output on each band, recording key down meter readings from amp and Palstar. This will also give me an indication if the problem is in the antenna/feedline systems. I will report results to the group.
Regards, Peter W2CDO Sent from my Verizon Wireless BlackBerry _______________________________________________ Drakelist mailing list [email protected] http://mailman.zerobeat.net/mailman/listinfo/drakelist
