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WG K7191 issues
retrocat:
i have a wg 25" k7191 i bought that was blowing fuses.
what i've done:
replaced electrolytic capacitors (cap kit), diodes (d19-d22), flyback, HOT, VR
i got it running but the screen had horizontal collapse.
i checked the yoke and it seemed okay, and resoldered the joints on the horizontal width coil.
my board (P538) has these metal film caps on the bottom that look pretty bad, could these be the cause of the problem? i can't seem to find any images online of a board with 2 caps on the bottom like this, but from researching i suspect they are C36 and C69? the markings on one of them are all but gone so i cant figure out the value.
retrocat:
also looking at this closer it appears to be a broken trace? there is no continuity between the 2 points marked with yellow
retrocat:
after looking at a bunch of stuff online i think i've figured it out.
i think the cap in the top of the photo is c69 and the bottom one is c36.
whoever put the c36 cap on also left the original 4 legged one on the top side of the board. so i think i need to remove them both and replace that one the proper way.
when i fixed the broken trace the fuse blew again.
i then found c37 is shorted which i think is the cause of the blowing fuse. i am going to replace it, c36, c69, and c38 while im at it.
grantspain:
the 4 legged cap needs to stay in as long as it reads ok, that looks like a factory mod
you should replace c37 if its bad and check d18
Zebidee:
It is quite common for those brownie caps to be added to a chassis to adjust horizontal width in particular. Capacitors in parallel add capacitance, and an easy way to add a cap is to put it under the board. If not added in the factory, it might be that someone has changed the CRT at some point and modded those caps to tweak the horizontal width.
So, I wouldn't remove them yet unless they test bad. Follow Grantspain's advice first.