Baby Pac-man lights

newthing34

Well-known member

Donor 7 years: 2013, 2020-2025
Joined
Nov 27, 2013
Messages
1,868
Reaction score
453
Location
San Jose, New Mexico
I have been fighting with getting all the lights working.
I am down to 12 not working.
I change all the light to LED, that got a lot of them working.
But not all, So on 3 of the ones not working I replaced 1N4148-Diode with no luck.
I cant on cuts in the harness
Any help would be grateful

Thanks
 
In a baby pac man, there's a solenoid /lamp driver board that handles the lights. It's on the back door, and has about 50 little transistors up in the left corner of it. With the game on, wiggle the connectors on the side of the board near those transistors and see if it makes any of the dead lights come on. If they do, you need to take the driver board out and resolder those connectors on the edge.

If that doesn't get it, make a list of the 12 lights that are out, and then look in the schematics and see which transistors run those 12 lights. Then look and see if all 12 of those transistors are ran by the same chip on that driver board.

12 out is a lot, whenever I do pinball machines I usually end up with 3 or 4 that don't work (on a Bally), if you've got 12 out and it's not the connectors, you likely have a driver chip that drives that whole area of the transistors that's died on you.
 
Thanks LyonsArcade & Shawn1976 Very very big HELP
There is a pattern with the lights that are out.
Shawn with the diagram you sent (A very big help) it looks to be in the driver board
which Lyon mentioned.
You guys are the best !!!

In a baby pac man, there's a solenoid /lamp driver board that handles the lights. It's on the back door, and has about 50 little transistors up in the left corner of it. With the game on, wiggle the connectors on the side of the board near those transistors and see if it makes any of the dead lights come on. If they do, you need to take the driver board out and resolder those connectors on the edge.

If that doesn't get it, make a list of the 12 lights that are out, and then look in the schematics and see which transistors run those 12 lights. Then look and see if all 12 of those transistors are ran by the same chip on that driver board.

12 out is a lot, whenever I do pinball machines I usually end up with 3 or 4 that don't work (on a Bally), if you've got 12 out and it's not the connectors, you likely have a driver chip that drives that whole area of the transistors that's died on you.





This should help you out.
Based off the attached photo which lights on the playfield are bad?
 

Attachments

  • Baby-Pac.jpg
    Baby-Pac.jpg
    167.7 KB · Views: 34
Thanks LyonsArcade & Shawn1976 Very very big HELP
There is a pattern with the lights that are out.
Shawn with the diagram you sent (A very big help) it looks to be in the driver board
which Lyon mentioned.
You guys are the best !!!

Not a problem.
At least you know now where to focus on when it comes to replacing those parts on the Solenoid board.
Attached a photo that shows the components you'll need to focus on based off of the numbers.
Good Luck!
 

Attachments

  • IMG_1430.jpg
    IMG_1430.jpg
    203.8 KB · Views: 38
Last edited:
Here's a helpful diagram of the pins upon installation.
"C" is "K" just to clarify.
 

Attachments

  • MCR106_Pinout.jpg
    MCR106_Pinout.jpg
    14.3 KB · Views: 29
  • 6116d95a.jpg
    6116d95a.jpg
    94 KB · Views: 25
Last edited:
Dokert made a great post on enhancing and pretty much bullet-proofing the lamps when it comes to the rectifiers. That and using LEDs should keep you in the game for a long time.

http://forums.arcade-museum.com/showthread.php?t=232992

Non-working lamps boil down to these reasons (common to rare):

1. Burnt lamp. Fix: Replace with LED.

2. Bad socket diode. Fix: Replace with 1N4004.

3. Bad rectifier, especially if the same numbered pair are out. Fix: Replace with MCR106-6. Better to replace all of them while you have the board out per Dokert's link.

4. Failing IDC connector to solenoid board. Fix: Replace the header and replace the IDC with molex. This really should be done for all IDC connectors.

5. Bad socket.

BTW - does anyone have a source for these sockets?

Edit: 87 t-66 also linked to Dokert's guide.
 
Last edited:
Read the pinrepair thread for Baby. You can ground one leg of the 2N5060 SCR transistor and see if the lights work. These SCR's fail easily. Especially if a diode goes or you try to play around with the playfield energized. It's probably a combination of diodes, SCR, and TIP102 transistors.

http://www.pinrepair.com/bally/babypac.htm

snippet from that page:

Baby Pacman Rectifier and Lamp/Solenoid Driver boards.
The power supply is a AS-2518-132 rectifier board. It holds the game fuses and is generally pretty robust and doesn't fail much. Unfortunately this board is different than the AS-2518-54 rectifier board used on Bally pinballs from Xenon to Cybernaut, but operates in the same manner. If you are familiar with the pinball -54 rectifier, you will feel right at home with the Baby Pacman -132 board.

The AS-2518-107 lamp/solenoid driver board often has problems. Most often the 2N5060 SCRs fail causing non-working or locked-on pinball playfield lamps. The 4514 lamp decoders (U1,U2) usually don't fail though. So if some playfield lamps don't work (and its not the bulb or lamp socket), suspect a 2N5060 SCR on the lamp/solenoid driver board connector. Note the color of the wire going to the problem lamp socket. Then find this wire color on the lamp/solenoid driver board connector. Then trace the connector its corresponding 2N5060 SCR. The lower leg of the SCR can be grounded, and the playfield light should turn on. If it does the wiring from the SCR to the playfield lamp is good, and the 2N5060 SCR should be replaced.
 
10 to 1 that it is your wiring. Replace all of those IDC connectors with Molex. If you don't you'll be chasing these lamps for a long time.
 
UP Date: Working great for now

Want to say thank you to all for the helping in getting baby pac up and working.
All the lights working nice, Spent the whole day playing it and not going to work.( Boss might be pissed ) Will see tomorrow. Dam game is hard but fun.
Well thanks every buddy.

Happy Holladay's
 
Back
Top Bottom