If it had a brightener on it, it is that dim, and the CRT bias voltages and HV are in spec, then may as well put the brightener back on and see how decent of a pic it can make and for how long.
B&W CRTs prior to ~1960 were often not nearly as bright as newer CRTs we are used to seeing....That said it does look dim for a tube of it's era.
I may have a good spare 21ALP4. IIRC I sold one this spring, and I think I had 2 before then.
Since the vertical is rolling and the horizontal is stable I'd suggest checking the vert and sync separator tubes, checking all resistors in those stages and replacing any that are out of tolerance.
|