Got a phone call from a customer wondering if I could fix his Bally Mata Hari (solid state) pinball machine. He said another repair person took the MPU 3.5 years ago to repair, and is still waiting for it. I told him that I would be happy to come and look at the game, and ended up bringing it to my shop. I had a MPU on stock and was able to start the repair right away.
I began the repair by checking fuses on the rectifier board, which were all good. The connectors and header pins had some burnt marks on them. I replaced header pin along with the connectors. The next step was to check the voltages, which all measured correctly. Plugged in the new MPU and game booted up.
Most of the lights, switches, and solenoids were working. I took apart the drop targets and cleaned the targets and adjusted the swtiches. The two top bumpers needed repaired with new skirts and spoons.
The left flipper bat was cracked and ended up replacing both flipper bats. The player 3 display was gassed, and owner said not to worry about it. I switched it with player 4 so three people could play a game on it. Score display 2 was missing the 10,000 digit and this was due to resistor r9 being open.
Finished up the repair by vacuuming the cabinet and playfield along with adding new rubbers and waxing the playfield. Tested the game and returned back to the owner. I was happy that it took less than 3.5 years to get his game back up and running 😁.
For a game that had sat for a quite a while, it was in good mechanical shape. All the solenoids worked and after replacing a handful of light bulbs, all the lights worked, too. I only ended up replacing one transistor.
The rules on the game are pretty basic, but can play the game with different goals in mind. One way is shoot for the “A” and “B” lights. This advances the horizontal lights (1K, 2K, 3K, 4K, 5K, Extra ball, and Special). The other way to play is to get the vertical bonus as high as possible with adding the bonus multiplier from the top saucer. Knocking down all the drop targets on one ball will light the outlanes for 50K and will light the special light, which requires knocking down all 8 drop targets again.
I was glad to get this game up and running again. The owner was happy to have it back working and his grandchildren can now play some games on it! I found two notes in the game and had to grab a picture of them.