Neotec S500 Vertical Hold Issue

putyoursoxon

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Donor 2022
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Working on a Neotec S500, havent been able to find any schematics for it. Heres the issue. Recapped the entire chassis, has a great looking image., but has an issue with the vertical hold. This happens on multiple different boards so I know thats not the issue.
The Vhold pot is super sensitive, but you can get it to hold. Had a slightly jittery image, but I replaced the tantalum cap at C307 and that took care of the jitter issue. Problem is although the hold is good if you turn it off and back on it will be off center. You can then use the pot to adjust it back to normal but as soon as it goes off again it will be off center again, not rolling just off center. I thought maybe IC301 LA7838, but I dont think that affects the sync, just deflection. Any idea what could be causing this? Picture attached for what it looks like when it comes back on. It will jump to a different location each time.
IMG_20240928_104727236_HDR.jpg
 
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