Pong Monitor Help

musicman282

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So I decided to recap the monitor in my quadrapong machine because the screen would randomly do this funky hula wave and it would cause me to miss the ball. I pulled the chasis out of the game and located the electrolytics, ordered some from mouser, replaced them and installed the chasis back in the game. Now it is doing what is shown in the picture and I can't adjust it out. It appears something is wrong with the sync. Anyone have any ideas of where I could start to troubleshoot this? Everything appears to be hooked up correctly since I took pictures before disassembly. I'm including pictures of the chasis. It's a Zenith, but doesn't have any model number stickers on it.
 

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hula

If it was doing the hula i would have started with the caps in the regulator area. Right now it looks like your horz freq is tweak to far.
I would start and look at your caps and see if they are installed(polarity) correctly. It has been awhile since i have work on those so i am guessing that they usually mark the caps back then with the positive and now caps have been marked with the neg side on caps.
Just a thought.
 
If it was doing the hula i would have started with the caps in the regulator area. Right now it looks like your horz freq is tweak to far.
I would start and look at your caps and see if they are installed(polarity) correctly. It has been awhile since i have work on those so i am guessing that they usually mark the caps back then with the positive and now caps have been marked with the neg side on caps.
Just a thought.

All caps have the correct polarity. I also was very careful to make sure they weren't shorting against anything since the components are just hanging off the back of the chasis and could easily short. I was thinking horz freq also. Problem is, I have no idea where that area of the circuit is because the schematics for this monitor are unreadable. I might just have to cough up the money and buy the sam's photofact to get this thing running again.
 
Got the Sam's photofact from the library and figured out that what I previously believed to be the horizontal width coil adjuster was actually adjusitng the horizontal hold. I twisted it a couple more times and Voila!! the picture locked in. Now I'm just curious as to how to center the picture on the screen. The Sams Photofact points to the yoke, but when I twist it the picture just becomes cockeye. What do I do to center the picture. This monitor doesn't have any position adjustment pots on it.

You can view the Sam's photofact for this Zenith 19EB12 here:

http://www.donkeykongkillscreen.com/1385-3n-2nd.pdf

All caps have the correct polarity. I also was very careful to make sure they weren't shorting against anything since the components are just hanging off the back of the chasis and could easily short. I was thinking horz freq also. Problem is, I have no idea where that area of the circuit is because the schematics for this monitor are unreadable. I might just have to cough up the money and buy the sam's photofact to get this thing running again.
 
If you just want to adjust the position. There should be two rings on the yolk with a metal tab on them near the clamp. moving them will move the screen image.
 
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