Saturday May 18, 2024

Mr. & Ms. Pac-Man Pinball - Working Again!
  Posted by: AceBHound on Jun 28th, 2012 8:31 PM
This past weekend I finally got around to redoing some of the AMP connectors (0.084" terminal pins) on the Bally Mr. & Ms. Pac-man pinball machine. The machine came non-working in a package deal my father bought a few years ago. Decent amount of wiring hacks, someone had obviously been trying to fix it. The MPU board also had a lot of alkaline damage, much more than even the non-working Hot Hand MPU I had cleaned up as one of my first board repairs in early 2010. My how time flies!

Anyway, somehow *miraculously* the MPU board didn't take a lot to get working back in 2010. I think a few components were noticeably corroded to the point they were disintegrating and once replaced the MPU board would boot most of the time. So some switches and other issues were fixed to get the game mostly working & many games of Mr. & Ms. Pac-Man were enjoyed. Over time the game got more finicky of course and eventually would "mostly not work" :) I expected this to happen though (as should anyone with an MPU board that has alkaline damage that hasn't been repaired).. but with as bad as the MPU board was it wasn't something I wanted to tackle until it fully died.

Luckily in the time that had elapsed several more Bally MPU boards were purchased that were in much better shape (but still needed to have alkaline damage cleaned up). I found a board that had light alkaline damage and it cleaned up very nice, put it in and the machine booted. But the displays were doing some weird stuff & couldn't start a game. I think attract mode would even lock up after a bit.

So, I assumed I still had board issues. Pulled the board, tested again at the bench where it seemed fine. Finally had to put it on the back-burner, knowing I had a lot of other connectors & wiring hacks to fix in the machine anyway. Some of the harnesses at the MPU had corrosion damage so I was fairly sure that was going to be a majority of my problem.

Fast-forward about two years (yeesh! -- well it got put in "storage" for a bit), and I've now got some quality crimping tools to get the 0.1" Molex connectors stripped & crimped fast. I took the time last weekend to redo the connectors at the MPU board, redo the AMP connectors at the power supply & low-and-behold the MPU board I had cleaned up and was still giving me issues is working just fine. Not bad! I had half-expected to be throwing one of the new DASH-35 MPU boards I'm building into the machine temporarily until I sorted out the board issues.

I kinda like this pinball. Always loved Pac-man as a kid, so it's instantly a winner there. The pac-maze on the playfield adds another element to the game. The maze is just a grid of dots in the middle of the playfield. You use the flipper buttons to control the direction of your yellow dot (Pac-man) and have to stay away from the red dot (ghost).. but the goal is to try to fill up as many mazes as possible. Each maze completed then counts as part of the bonus. Pretty neat for its time.

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