OK, temper tantrum over, lets fix my Mr/Mrs Pacman

kaz1961

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Alright you guys talked me into it, lets get these flippers working. The MPU and solenoid boards were rebuilt by Chris Munson so I am sure they are not the issue. I also swapped this solenoid board into another game and it worked 100%. I did a playfield swap and the flippers worked before the swap. After the swap they worked for a few games then died. I disconnected the connectors and they worked for a few seconds then stopped again. I get 60VDC at the lugs which is high but I dont know if that could be the problem. When I ground the lug at the coil the flippers do not fire as pinrepair says they should. When I ground the lug at Q15 on the solenoid board I can hear the flipper relay click and if I leave it grounded the flippers will work with the flipper buttons. I am guessing a connector or wiring issue at this point. Any ideas where to go from here? Working tonight so I cant get to the game until about 11 PM.
 
When I ground the lug at Q15 on the solenoid board I can hear the flipper relay click and if I leave it grounded the flippers will work with the flipper buttons.

Sounds like you've got a problem with the drive circuit driving the flipper relay. Does the flipper relay turn on when you start a game? Does it click when that drive circuit is energized in solenoid test? My guess would be the answer is no to both of those based on what you're saying.

In short: if the flippers work with the tab of Q15 grounded the problem is with Q15 or the circuit behind it.
 
Sounds like you've got a problem with the drive circuit driving the flipper relay. Does the flipper relay turn on when you start a game? Does it click when that drive circuit is energized in solenoid test? My guess would be the answer is no to both of those based on what you're saying.

In short: if the flippers work with the tab of Q15 grounded the problem is with Q15 or the circuit behind it.

If that were the case then the board wouldnt work in other games, right? This board works great in other games. I also swapped in another working solenoid board and the flippers dont work with that board eithed.
 
If that were the case then the board wouldnt work in other games, right? This board works great in other games. I also swapped in another working solenoid board and the flippers dont work with that board eithed.

You're right. I guess I missed that part :p

I still think your problem is with the flipper relay drive circuit... but beyond the driver board.

So... does the flipper relay energize when you start a game or when Q15 is energized in solenoid test? If not then the "flipper disable" signal from the MPU might not be making it to the driver board (connector problem) or the pin could be stuck high on the PIA (pin 16 - U11 of the MPU).

Remember that the "continuous" solenoids are each triggered through an individual PIA pin unlike the "momentary" solenoids that are driven through a 4-to-16 decoder. If the PIA pin is stuck high or the connection between that pin (through socket, connectors, headers, etc...) fails the flipper relay will never be told to turn on and the symptoms should be exactly like what you're experiencing.
 
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test EOS switch with multimeter, install new ones if contacts are pitted or worn

unsolder Q15 and remove from board, test on diode test

follow wires/continuity test them from one end to another to see if broken wires are where you cant see them

inspect fuse holders. just because it looks ok doesnt mean squat. could be weak and not letting enough electron flow to operate flippers

good going grasshopper, let us know what you find
:)
 
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Im glad you got back on this. Im sure im not the only one who has come close to giving up on a project, but when you make it through, you will feel great, and will have the confidence to fix any other issues down the line. You will know that game inside and out!!! keep truckin, or just take a week break, but dont give up!!!
 
test EOS switch with multimeter, install new ones if contacts are pitted or worn

Definitely worth checking as a preventative maintenance item but EOS switches won't cause this problem.

unsolder Q15 and remove from board, test on diode test

Q15 can be considered good because the board works fine in another game.

follow wires/continuity test them from one end to another to see if broken wires are where you cant see them

The fact that the flippers work with the flipper relay manually energized tells us that the cause is not a wiring/connector problem going out to the flippers but connectors and wiring are still worth looking at in general.

inspect fuse holders. just because it looks ok doesnt mean squat. could be weak and not letting enough electron flow to operate flippers

Again I agree to check them but again we already know they're not causing the problem.

pinrepair.com covers preventative maintenance on Bally games in pretty good detail.

The fact that the driver board works in another game but a known good driver board doesn't work in this game point to the circuit that drives the flipper relay external to the driver board. That circuit originates at U11 on the MPU, goes through a socket and some connectors and ultimately ends up at the flipper relay drive circuit on the driver board.

What we really need to know is if the flipper relay is energized when you start a game. I suspect it's not.
 
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I dont hear the flipper relay energizing when I start the game.

You could try swapping U10 and U11 on the MPU (6820/6821 PIAs). If that solves your problem either the PIA is bad (pin 16 stuck high or open) or the socket is bad and re-seating the IC solved the problem temporarily.

If that doesn't solve the problem I would check for continuity between pin 16 of U11 on the MPU and either end of R37 on the driver board. Note that when checking one end of that resistor you will also be reading the resistance through the resistor (3.9K). One end of the resistor should read close to 0 ohms and the other should read approx 3.9K with the other meter lead on pin 16 of U11 on the MPU. That will check continuity right from the PIA pin to the input of the solenoid drive circuit that drives the flipper relay. If there's no continuity you'll have to figure out where it's broken. Probably one of the molex connectors.
 
Definitely worth checking as a preventative maintenance item but EOS switches won't cause this problem.
Q15 can be considered good because the board works fine in another game.
The fact that the flippers work with the flipper relay manually energized tells us that the cause is not a wiring/connector problem going out to the flippers but connectors and wiring are still worth looking at in general.
Again I agree to check them but again we already know they're not causing the problem.
pinrepair.com covers preventative maintenance on Bally games in pretty good detail.
The fact that the driver board works in another game but a known good driver board doesn't work in this game point to the circuit that drives the flipper relay external to the driver board. That circuit originates at U11 on the MPU, goes through a socket and some connectors and ultimately ends up at the flipper relay drive circuit on the driver board.
What we really need to know is if the flipper relay is energized when you start a game. I suspect it's not.

played the game a few times at an auction about a year ago
thought it was a fun game

would like to play one again if i ever see another one

let us know what the fix is ????
 
someone can probably remember better than I can, but I believe the ground for the flipper relay comes in on the upper left side of the solenoid driver board and sends the ground over to the relay from the cabinet flipper switches. If you ground the center lug on a flipper coil for a moment, it should fire.
 
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