25k7000 7100 stripes i.e. “dark vertical bars”

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I replaced all the caps, including the filter, except the 3 bipolars. The troubleshooting guide says to replace C57 (already replaced) so I grabbed one from another cap kit and swapped it in. I'm still getting the stripes, though. Where should I go next with this thing?

IMG_0946.jpeg

IMG_0945.jpeg
 

TLDR: Replace C204 with a 22uf 160v cap. If it's original, it's likely a ceramic cap. I've gone as high as 47uf for very faint stuff.
 

TLDR: Replace C204 with a 22uf 160v cap. If it's original, it's likely a ceramic cap. I've gone as high as 47uf for very faint stuff.

Dang it. After reading the thread, I thought for sure that was it. Swapped out the cap, but nothing changed. That diagonal line is also an artifact of this chassis. The tube looks great with a chassis pulled from another cab.

IMG_0948.jpeg
 
Hmm, C57 seems to be the main culprit for jail bars in the flowchart, other than c204.

You said c57 is new, so maybe look at the schematic and check everything adjacent, looks like c23 is nearby, and also c57 is close to ic2&4. Also R89 & 101. Would just check all the power section stuff to make sure it's solid.

Are we sure the c57 is a good quality cap?



IMG_3421.jpeg
 
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those are B+ filter failure symptoms (jailbars and the bright on left dark on right). wild that you're getting the same thing with multiple caps. now that I've gone public with how I work on these maybe you should find the R101 section part and try that out. lol

does turning flyback screen up/down change it at all?
 
those are B+ filter failure symptoms (jailbars and the bright on left dark on right). wild that you're getting the same thing with multiple caps. now that I've gone public with how I work on these maybe you should find the R101 section part and try that out. lol

does turning flyback screen up/down change it at all?

Turning the Screen dial doesn't change the jailbars. The screen darkens evenly, leaving the brighter lines still more visible than the rest.

I couldn't find the reference to the R101 section you mentioned. Was that in a video you did?
R101 tests good. I replaced C23 (again) with a cap from another kit, and reinforced the traces in the area. No effect at all.

Maybe the LA7823?
 
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