A friend of mine is looking at purchasing a used Titan from an estate sale.
It's not been used in a while. The seller claimed to have recently tested it
at 1KW out. He did state that there appeared to be a problem on 15 meters.
I did notice that the factory installed collar to keep one from turning the
band switch to 10M had never been moved from the blocking position.
When first turned on the amp blew the PS fuses (think they were not slow
blow). When it started up without blowing the fuses, and it came off the 3
minute warm-up, it showed .3 amps plate current without being keyed. The amp
was opened up and tubes pulled, blown out, visually inspected and some
corrosion on the plate cap connections was removed. When turned back on, amp
starts up normally (like mine), HV seems right and it seems to be keying
correctly in QSK with a TT Omni 6 with the amp feeding a dummy load.
The problem - no output with 20-30 watts in, no movement of the grid current
meter or plate current meter, no dip in HV supply when keyed in CW. Input
SWR on 20 was 2 (mine is 1.1-1.2) .
I've set the amp down next to mine and compared the two. Other than a few
component changes (mine's probably a few years older), we could not see any
significant differences. The amp did not perform any differently on my PS
than it did on it's own (and yes - my PS still works).
Is there any easy way to tell if the tubes are shot?
Can the amp be run with just one tube at a time to test each tube?
How much risk am I taking if I try my good tubes in his amp???
Any ideas of what else to look for?
I've owned about 10 different used amps with various tubes and never had any
significant trouble. Can't say that for the numerous used HF radios that
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