I was testing a Henry 3k Classic which had been sitting idle for a few years.
Amp tuned up fine on 40metrs with the HV in the CW position. In the SSB
position, after keying down just long enough to check the Bird meter, the
built-in pwr switch/breaker would trip. Output was about 1200w for 75w
drive. HV was reading 4400v no-load, 4100v key-down, with about 600ma on the
plate current. After the breaker was reset, all was fine again in the CW
position. When we tried the SSB position again, same thing - tripped pwr
breaker switch.
Are 3cx1200's known to go gassy from sitting idle for years at a time ?
Visually all looks ok inside. Test was into a dummy load. My only guess is
that the tube is flashing over, or something is going awry. No damage, just a
tripped breaker.
Any comments ?
Thanks
Eric
KK2ED
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