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CRT (Makvision) image is a large bluish blob. Dead, or repairable?
Zebidee:
--- Quote from: Baldbull on February 25, 2021, 08:01:41 pm ---IT WORKED!!!!!!!
Now I just have to find this damn transistor I broke... 2SA1371-E
if only I'd have started with the tube.
--- End quote ---
Well, grantspain did say that up front (desolder blue gun pin) ;)
I'm just happy it seems to have fixed the problem, you can never be sure. But for today, percussive repair techniques rule! :cheers:
jennifer:
Glad it works...problem solved.
jennifer:
After some thought...I have to be of the opinion that smacking that tube with a brommhandle is not fixing it, and now that it is working the problem has been made more difficult to track down as a done out the door fix, and to isolate the short now you are looking at a mutiburst pattern generator as to have some control over the color and refind the original problem not to mention the other guns haven't been cleaned or balanced...Not everyone has a rejuvenator this is true, but if you can't find one cheap, you just ain't trying very hard, or flat out don't even want one...If I was to guess, that tube will be worse next time, and will most likely even burn the screen.
Zebidee:
Seeing as it must be silly season, how about we try hitting a CRT "home run" with a baseball bat then? Maybe that will improve things? Of course I am being ridiculous, but just continuing the hyperbole.
For giggles I decided to look up rejuvenators for sale (again, I do it occasionally). As usual, almost all listings are in the USA, and they are all ancient tech so I worry I'd spend more time fixing it than using it. Best option I could find that was close to me was in Singapore, US$297 + $134 shipping, fairly typical (LCT-910A). Chump change for some but serious money for me. Still...:
https://www.ebay.com/itm/CRT-tester-Leader-LCT-910A-Cathode-Ray-tube-tester-rejuvenator/323878499016?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160727114228%26meid%3D87a407f9f94c43479b1f77dd3443b8cd%26pid%3D100290%26rk%3D1%26rkt%3D3%26sd%3D323878499016%26itm%3D323878499016%26pmt%3D0%26noa%3D1%26pg%3D2060778&_trksid=p2060778.c100290.m3507
Of course in the USA, land of milk-and-honey for arcade enthusiasts, I could maybe grab a B&K 46X for around $150 or even less. Drive around the corner to pick it up.
I've never owned a rejuvenator, but have done some research and watched some YT vids on them. Something that stands out is that while they can maybe (or maybe not) breathe new life into a tube for a few months or years they can actually damage the guns and filaments and that rejuvenation is really a "close to end-of-life" option. Still, nice to have and good for other things like diagnosis or CRT health etc.
dmckean:
Considering arcade cabinets and TVs tend to sit in one place for years at a time, moving the problem down the road a decade is basically the same thing as fixing it. For most of us at least. By the time this becomes an issue again, the tube may be ready for rejuvenation.