The Titan III linear failed (what else is new) after the ARRL SSB contest. No RX, high TX SWR. We traced the problem to the SWR board (pictured). It turns out that there is an RF short between the pin and ground of the coax. This should seem easy to find, but it is proving to be very tricky. We proved beyond doubt that both T/R relays are perfect. I isolated both SO-239s and there is no short in either of them. I proved it is not the SWR transformer. Then I ran out of time. Now I suspect there is a short somewhere in the rectifier circuit that picks off RF and drives the SWR indicator. I brought the board to Idaho. Does anyone want to take a crack at this repair? I'll send you the board.
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