Post cap-kit EZ20 problem.....

nomore25s

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Picked up a donkey kong on the cheap. Had some issues, I'm restoring it, almost finished.

Okay, working monitor, but too dim. Sound amp was screeching, capkit=working perfectly now.

So I installed a BobR EZ20 plus capkit. I was being extra careful and have doublechecked I didn't install any backwards. No lifted pads, nothing out-of-the-ordinary.

B+ adjusted to 108vdc, perfect.

Brightness seems fixed, I think.

But, I get the following, any suggestions? I tried POTs on the little pcb, I tried the POTs on the DK PCB. I get movement/changes, but this is as close to anything I can get.
 

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There is an adjustment in the middle of the chassis that should fix that. I think it's the h-hold. - Barry
 

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Howdy! I just went through the same problem. You can read about it in this post; http://forums.arcade-museum.com/showthread.php?t=176776. Of course try the H hold first in combination with the other pots. I could not get a picture no matter what I did. I finally re-capped the chassis again, but this time I checked all of the old as well as the new caps. I have never bothered to check new caps but I will in the future for peace of mind. The NP caps are rated at 4.7uf 25v (there are two of them). One of the caps that I took out read 5.9uf which is over the 20% tolerance range. I do not know if this difference would cause the trouble that I was having but the monitor now works with a great picture. I also bought my kit from Bob. Maybe the experts can make sense of this. Good luck!
 
Thank you Barry!

Perfect!

I owe you! Someone needs to add that to the EZ20 flow chart for us dummies!
 

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Howdy! I just went through the same problem. You can read about it in this post; http://forums.arcade-museum.com/showthread.php?t=176776. Of course try the H hold first in combination with the other pots. I could not get a picture no matter what I did. I finally re-capped the chassis again, but this time I checked all of the old as well as the new caps. I have never bothered to check new caps but I will in the future for peace of mind. The NP caps are rated at 4.7uf 25v (there are two of them). One of the caps that I took out read 5.9uf which is over the 20% tolerance range. I do not know if this difference would cause the trouble that I was having but the monitor now works with a great picture. I also bought my kit from Bob. Maybe the experts can make sense of this. Good luck!

Thanks - looks like I just needed to adjust vr451.

Anyone know its rating? It seemed a bit touchy, I might order 1 or 2 to have on hand.
 
I thought I put that in the flow chart, guess I ran out of room and left it out.

No problem - it is still great to have as is. Just the parts about adjusting/checking the B+ is useful!

I have another chassis that I capped a while ago and with what I've read it might be in HV shutdown mode. I wonder if it is simply a B+ adjustment!

Thanks again!
 
No problem - it is still great to have as is. Just the parts about adjusting/checking the B+ is useful!

I have another chassis that I capped a while ago and with what I've read it might be in HV shutdown mode. I wonder if it is simply a B+ adjustment!

Thanks again!

For some strange reason the damn B+ pots fail almost like when you recap a GO7 with doing the flyback.
 
lol

Bob should include a B+ pot in with the cap kits. :p

hell I'd pay a dollar more...

never had to use that other H-Hold before, strange.
 
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