Space Invaders M5000 KV700 Vertical Roll

neopolss

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Donor 6 years: 2013, 2016-2020
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I've recapped the chassis, as well as replaced the two vertical pots. I've also subbed in new caps for the large can cap, but I am still getting vertical roll on it. If I adjust the pots I can get the image to *almost* stop rolling, but I can't get it to quite lock in. Any advice on where to look?
 
according to the troubleshooting guide I have it says you should check

transistors
Q10, 11, 12, and 13

Diode
D12

and caps
C34, 35, 37 and 38 It doesn't look like any of those are in the standard cap kit.
 
Thank you. I will just shotgun all the parts and let you know what happens.
 
Following up. I replaced Q10 with a cross referenced NTE159, replaced Q11, Q12, & Q13 with NTE123AP. I replaced poly caps at C37, C38, C36. C34 & C35 are not present on the KV700 board. That got me a slow rolling picture. Quick adjustment of the pot showed the game attempting to lock-on, but only for a few moments. So I knew that my problem now was probably poor sync. I pulled the sync wires from the molex and made a direct connection. Sync is now perfect. Monitor is now running good.
 
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