08-06-2010, 10:00 AM
The 7X7 is same as XXFM tube. Test for filament continuity (pins 1 and 8 of the tube, and it's socket as well for filament voltage.) This is a small signal tube, and will not become very warm in use if it is good.
You can get a schematic on this forum.
Replace all the electrolytic capacitors, as well as the paper ones as well. They're over 50almost 60 years old!
More help available here and elsewhere.
You can get a schematic on this forum.
Replace all the electrolytic capacitors, as well as the paper ones as well. They're over 50almost 60 years old!
More help available here and elsewhere.
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