[R-390] R-390A and the Selenium Rectifier

[K2CBY@aol.com]

I had the selenium rectifier fail one leg to open on my Motorola Contract 363-PH-54 chassis about 10 years ago. No short, no smoke, no smell. The symptom was a very loud buzz from the antenna relay and a failure to pull in completely when the FUNCTION was switched to CAL. I assume the same symptom would appear if BREAK IN was enabled and the ptt line grounded. The symptoms of a failed selenium rectifier are so obvious and it is so easy to get to that I wouldn't bother with pre-emptive replacement.
Miles, K2CBY, Sag Harbor, NY