Hi all, does anyone have any very old CRT cross-reference around? I probably need to replace an Amperex M24-302W 9" CRT on a vintage CBM PET 2001 and probably these CRTs are unobtanium now. Maybe some old monochrome TV CRT could be substituted? The tube has probably a cathode to heather short. Even with the cathode lead grounded, the screen is all white with brighter retrace lines. G1 sits at -32V so, it's not a matter of wrong bias or something similar. Cathode signal generated from the monitor CRT is positive and about 0V should cutoff the beam, according to the schematics. Might be a failure on the HV generator that gives too high voltage, I'll measure it later (shoud be 10 KV), but I think if it was that, it would kill the flyback transformer quickly, isn't it? Frank
- posted
6 years ago