recapped go7- screen curl

pinnut

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just recapped a go7- has a screen curl. was also there before the cap, but not in quite the same way. also i cant center it. it is a centered as i can get it without losing it all together. see pic. any ideas? use a different value cap? i did do the curl mod. the pic with the fluke meter in it is a before cap , the pic with no meter is after cap. notice the curl seems to go in an opposite direction in the second pic.

thanks
 

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There are several things I would consider when seeing an image like this.

Do the curl mod (22uf cap is better than 10uf imo).
What is the b+?
Did you put a 220 uf in both 517 and 518 (ones next to the flyback, I may be wrong with the #'s)
Check the 2 reistors up the left rail of the chassis (r314, r317 iirc), make sure they are like 220 ohms not 2000ohms. (I need to recheck all these #'s , I'm trying to go from memory).

Other things I always consider as well:
New flyback?
Hfreq pot changed?(all 4 chassis pots for that matter).
Test the chassis with a pcb also, when
I use the tpg (for example), it can look distorted, but with a game pcb it looks virtually perfect.
 
1: Measure B+ voltage to be sure it is at correct voltage.

2: Check resistors R314 and 317. Both should be 390 ohms @ 1/4 watt. These are in the negative sync circuit. The factory had sent quite a few chassis out that had the wrong value resistors installed in those positions.

3: Some people have found that when doing the curl mod, use a 22 uf capacitor instead of a 10 uf one. Seems to help quite a bit in some cases.

4: When you did the capkit, did it include the bi-polar (a.k.a. non-polar) caps at locations C301 and C520? They are both 3.3 uf @ 50v non-polar.

5: C517 and C518 should both be 220 uf @ 25 volts. Originally C517 was 100 uf. This helps the picture to be more squared and not have a "pincushion" or "barrel" look to it.

6: Try moving the horizontal centering adjustment jumper wire. There are 3 positions you can set it: Left - Center - Right. Make sure you're putting the jumper wire on the correct horizontal adjustment tabs and NOT on the vertical adjustment tabs or serious damage can occur.
 
B+ is 120. i changed the cap to make both 220, up the cap on the curl mod to 22.
both BP caps changed with the kit. its a little better, im going to try it in the game.

thanks
 
its in the game, no curl. the game board isnt great. i had a real hard time getting the horz to hold still. it would just about stop, a teeny tiny turn more on the pot, and it would start rolling the other way. i pulled the board, reseated everything ,cleaned the edge connector, and now it holds, colors are not right though, the maze( ms pacman) is hard to see.
 
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