'82 Bally GI light dimming problem

dasvis

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My '82 Mr & Mrs Pacman has developed a problem with the GI lights. They will randomly flicker & dim when the flippers are activated- not always & mostly when it's cold. My first guess is a bad ground, but ???
 
My '82 Mr & Mrs Pacman has developed a problem with the GI lights. They will randomly flicker & dim when the flippers are activated- not always & mostly when it's cold. My first guess is a bad ground, but ???

Connector problems.

I would start at the rectifier board but the grounds at the lamp driver board are suspect as well. Connector problems are common throughout those games.
 
Connector.
The male pins on the GI flasher board had broken solder joints around all of them. Re-flowed & added a bit of solder & all is well.
Next question, if it has a flasher board, should not the GI lights flash in attract mode?
Found this on Clay's pinball repair site:

"I am working on a Mr/Mrs Pacman, and I notice the GI (general illumination) lamps flash on and off at certain times during attract mode, but does not come on during game play."
To make the GI lamps flash on and off, Bally used a Triac bolted to the power supply board in the cabinet. The triac is cycled by the GI lamp flasher board mounted under the playfield. This flasher board is similar to a solenoid expander board. The output of a lamp SCR driver is used to drive a MOC3011 opto coupler that drives the Triac. As with the solenoid expander board, a dummy 555 lamp is connected to the SCR output on the flasher board to insure there is enough current draw to drive the MOC3011. Most likely this 555 bulb is burned out, and causing your problem. Also check the flasher board for bad (cracked or cold) solder connections. Check all the cable connections to the triac too. Lastly you can replace the MOC3011 chip.

Just for the hell of it I ordered a MOC3011 chip, but I could not find the Triac listed anywhere. What is the most likely component to keep the lights from flashing?
 
Replace your connectors with new pins AND headers on the printed circuit boards. Need to reduce the resistance there. Also, do the mods in the repair guide, like upgrading the bridge rectifiers.
 
Replace your connectors with new pins AND headers on the printed circuit boards. Need to reduce the resistance there. Also, do the mods in the repair guide, like upgrading the bridge rectifiers.

Rectifier board has been totally rebuilt, will replace connectors!
 
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