Battlezone display not adjust correctly

Those are the raw waveforms for X and Y, and when not in XY mode you are plotting their amplitude versus time. Go back to the settings that gave you the small square, and change only the two knobs on the left to a smaller volts per division (a few stops clockwise) and that should make your small square into a bigger square.

Viewing the raw waveforms can tell you if the board is putting out appropriate signals (and yours are in the ballpark), but for the issue you describe it would be difficult to use them to verify the board is generating a perfect image. The goal here is to use the scope as a known-good vector monitor, and see if the issue persists (e.g., is a game board issue) or if the image is fine (e.g., is an issue with your monitor).

Success!

It looks the same as it does on my other display. Now I assume I should try to adjust the XY pots on the game board or is it enough proof that it looks the same on this display?
 

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I'll go back to Douglas's post #2. If your YBIP is maxed out, and the picture is still not straight (and the pot is not broken or dirty), you have a bad analog chip in the video section.

I'd take Douglas's recommendation and try to 13201 first, for the y-axis. If not that, then the TL082 next.
 
Success!

It looks the same as it does on my other display. Now I assume I should try to adjust the XY pots on the game board or is it enough proof that it looks the same on this display?

You can try but if it exactly mirrors the display (aside from the connecting lines that the scope draws but the monitors omits) and you've tried adjusting it there, then you'll also be unable to get it right on the scope. You have a board problem.

Did it occur spontaneously? Or after any handling of the game board? There are some chiclet-looking capacitors that stick up out of the analog section of the board (where the adjustment pots are) and a broken one of those could cause your issue. It's something in the Y axis.
 
I'll go back to Douglas's post #2. If your YBIP is maxed out, and the picture is still not straight (and the pot is not broken or dirty), you have a bad analog chip in the video section.

I'd take Douglas's recommendation and try to 13201 first, for the y-axis. If not that, then the TL082 next.

Thanks for the help!
 
You can try but if it exactly mirrors the display (aside from the connecting lines that the scope draws but the monitors omits) and you've tried adjusting it there, then you'll also be unable to get it right on the scope. You have a board problem.

Did it occur spontaneously? Or after any handling of the game board? There are some chiclet-looking capacitors that stick up out of the analog section of the board (where the adjustment pots are) and a broken one of those could cause your issue. It's something in the Y axis.

It's an exact mirror yes. Thanks for the help! I got a lesson in scope use and have my next steps. Thanks!!
 
Did it occur spontaneously? Or after any handling of the game board? There are some chiclet-looking capacitors that stick up out of the analog section of the board (where the adjustment pots are) and a broken one of those could cause your issue. It's something in the Y axis.

Somehow I missed this bit of your response. I didn't touch the game board at all. I noticed it one night when I went to play it. I do have this on a power strip with three other arcades. I use the power strip to power the games on and off. It's a 20 AMP circuit they are plugged into. So, I am not sure when it happened... It could have been up to maybe two weeks before I noticed.
 
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