Sanyo 20EZ purity issue?

Ace20

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I've just fully recapped a Sanyo 20EZ and replaced all the pots and it looks so much better than it did but I've noticed what looks like a purity issue in the bottom right corner. The first picture of Mario is what he looks like in bottom left, top left and top right corner but in the bottom right corner he has a sort of ghosting issue shown in the second picture. The second picture didn't come out very well but basically it looks like the colors don't line up.

The image was so bad before the capkit so I don't know if it had this issue before but I don't think it's a cap issue I was very careful to tripple check values and polarity. I didn't think bad purity would cause this in just one corner though? could this be fixed with the pots on the neck board? I just tweaked everything until it looked good I don't have a tpg or any thing at the moment to do a proper calibration.

I also noticed a bit of noise and it's a bit unstable at times but I suspect that's the 40 year old flyback?
 

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Could be.

I would rotate the monitor/cab while it's on to make sure it's not just a degussing issue.

Also check the rubber wedges near the yoke and make sure none came lose when you did your recap. You can buy small magnets that sick on the back side of the tube for small corrections.

Yoke adjustments can be complicated and you can messed up a good monitor fast if you're not careful. I'd slid the entire yoke front or back first before messing with the ring adjustment. Mark the existing location of all the rings and yoke so you can return it to the starting point if all else fails.
 
I wouldn't touch the yoke yet. I bet this is just a simple convergence issue in just one corner of your tube. Potentially an easy fix with convergence strips.

If this is the only corner where RGB are not aligning, then convergence strips are the answer.
 
if it was purity or improperly positioned yoke you'd get magnetic splotches in places. you could muck with the convergence rings but they're so old and probably very brittle now I'd be afraid to try spinning them. I had to fix convergence on a U5000 or K7400 tube a couple weeks ago and those rings barely would move. I got it about 94% right and just said that's it, and left the focus very slightly blurry to help mask it being off on the whole left side of the screen.

so I would suggest convergence strips or just live with it.
 
Getcha a degaussing wand and see if it goes away. Might be as easy as that.

Jason
 
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