1991 Data East Batman – After repairs

A gentleman contacted me with his 1991 Data East Batman machine. He had purchased from a friend and it had been playing, but it had been several years sitting and was currently not working. He wanted to get it back up and running again, so I went to take a look at it.

Having sat for some time, it had a lot of minor and one major issue from what I could tell giving it a quick look over. Being that this had a lot of potential issues I wouldn’t notice until giving it a thorough examination, I requested that he bring to my home workshop for repair rather than trying to do an in-house fix.

Here’s a list of what issues I found this one:

– Broken shooter rod

– Ball trough was only recognizing two of the three balls

– Added revised game and display ROMs

– Display worked intermittently, and even when working, was not computing correctly

– Receiving “Open the Door” message when display intermittently worked

– VUK switch from Flugelheim wasn’t registering correctly

– Needed a full shop with new rubbers, balls, lamps and polish/wax

– Trough auto-shooter coil locked on

The shooter rod and shop job were obviously easy enough. The “Open the Door” message

Changed Game ROMS and new RAM

on Data East games points to the game’s RAM not retaining the needed 4.5 volts to hold memory for high scores, settings, etc. Sometimes a switch of the three “AA” batteries will resolve this issue and should always be the first thing you check. After swapping the batteries to no avail, I traced the voltage down through the blocking diode at D25 and down to pin 24 on the 6264 RAM at 5D. The game was getting proper voltage all the way down the line, which points to a faulty 6264 RAM. I replaced the 6264 RAM which is already socketed and this resolved this issue.

The ball trough issue was a broken 1N4004 diode on one of the trough switches. These diodes work to protect spikes that could be sent back to the boards when the switch is engaged. If broken or faulty, they can cause switch and/or switch matrix issues.

The VUK switch underneath the Flugelheim was maladjusted and staying stuck in the closed position. It took several manual mechanical adjustments to make sure the spring mechanism on the ball popper worked, but once adjusted, the VUK performed correctly and allowed for multiball and jackpots as it should.

Replaced TIP36C

The fuse at F5 on the PPB board was blowing on start up. This fuse is in line with the 50vdc that provides power to several coils and the flippers. The coil tested good, which was nice as it’s the most expensive part in the circuit. However, the 1N4004 diode did test out of spec, so I replaced it; however, still blowing the fuse. Tracing further back, I tested the TIP36C and, sure enough, it was faulty. I pulled the PPB, replaced the TIP36C and that resolved that issue.

The final and most perplexing issue this game exhibited was the display issue. With Data East games the CPU and Dot Matrix Display run separately in that the display has a CPU which boots the display ROM and the CPU boots the game ROMs. This game, upon boot up, would boot the display ROM but never the game ROM. It would show the correct display version and then go blank, sometimes to reappear but would not be showing the correct animations.

Socketed and replaced display PIA

All voltages to the display were in spec. I replaced the ROMs, both game and display, first to no avail. Then, I replaced the ribbon cable from the CPU to the display with a known working one off my Jurassic Park. After that I used Leon’s Test ROM on the CPU to test the 6821 PIAs. The display PIA actually tested faulty, so I removed and socketed and replaced with a 65c21 (as 6821s are almost obsolete these days). Surely this was the fix….nope.

Thinking now it had to be the 128×16 display, I took it to my buddy Jack’s place who had a Hook that uses the same small display (there are only five games released with this display, all Data East from the early 90s). In his Hook, the display worked! I borrowed his power supply board and brought it home to test. Even though all voltages read fine on this game, it was the power supply causing the issue. I had reseated all the cables first thing and all voltages were in spec, but I did find one of the big block resistors out of spec and one capacitor that needed replacement.

Finally, the display worked! I play tested about 10-12 times to make sure everything worked correctly. Game is headed back home this weekend, and my initials may or may not be the high score from one of the play tests 🙂