Bootleg Ms. Pacman acting funny. Advice Need.

Gaetznes

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Ok, i'm trying to help my friend. But its the blind leading the blind here.

Whats happening is, the maze is visible and the music still plays. But you can't see Ms. or any Ghost.
 
One of the roms in row 5 on the real board creates the characters, you may have a problem with that chip, or the lines to that chip, or the buffers to that chip, or the ram that interacts with that chip.
 
Try cleaning the ROMs - they would be the ones with stickers on them in the photo, and the ones next to them in the photo to the left, which appear to have windows (to write to the EPROMs).

Carefully remove Rom 5. You can also try to influence / verify you have the right one, by powering the game up, and then pressing on the various ROMs while someone looks at the screen to see if it is changing.

Note: This may or may not work, depending on the corrosion that is present.
 
There are several chips that could cause this problem. The 7489 rams are one suspect. Note there may be 4 on the board, 2 of them are sound and the other two are the object rams. Usually if its an eprom you will see a colored block instead of the character, even with the rom out of socket. If you see nothing at all I would suspect the ram or associated chips. On a midway board the rom would be 5E. Not sure which one it would be on that bootleg as I rarely work on bootleg boards.
 
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