07-26-2014, 01:54 PM
Pilot
Yes it could be a tube even though it tests good, let alone the fact some testers do not even test mutual conductance, but even if they do you might have a problem, just like the one I have fixed a week ago, looks like grid leakage.
If it applies to phono and RF, I would start changing from Phono preamp tube and proceed down to the audio driver tube by tube. I do not have 53-1750 but if 53-1754 is any similar, there are 4 tubes to try.
Yes it could be a tube even though it tests good, let alone the fact some testers do not even test mutual conductance, but even if they do you might have a problem, just like the one I have fixed a week ago, looks like grid leakage.
If it applies to phono and RF, I would start changing from Phono preamp tube and proceed down to the audio driver tube by tube. I do not have 53-1750 but if 53-1754 is any similar, there are 4 tubes to try.
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