Sega G-80 (Pengo) Power Supply

csbartz

New member
Joined
Jun 23, 2009
Messages
175
Reaction score
0
Location
Lakewood, Colorado
I'm trying to get my Pengo up and running and I have determined there is a problem with the original G-80 power supply. Measuring +5 and +12 without the game board connected I get +5.1 and +11.98. All good. Hooking up the PCB drops the +5 to +1.9 and the +12 stays about the same. The PS board looks pristine with no charring or really anything bad looking.

Which parts should I be testing? All diodes and fuses test fine. The TIP141 looks like it provides the +5 -- is that correct? Any other parts that could cause the drop in voltage?

Chris
 
Ps prob

I would imagine your powersupply needs rebuilt. I dont think the board would drag the voltages down otherwise. Mine was doing the same thing when I got it. I made some connectors for my Pengo and put in a switcher. I was going to get back to it but that was 2 years ago. So... I cant offer more help than that.
 
I wired in a switcher and the game came up perfectly (well, the picture was upside down but a yoke flip fixed that :)).

I've adjusted the pot on the switcher and the best I can do is +5.04 and +12.7. Is that too high for the +12?

I'd still like to fix the original PS but this will do for now.

Chris
 
In my experience it's typically just a matter of replacing the TIP141. If that doesn't fix it, the LM723 and/or 2N4403 would be the next suspects.
 
Back
Top Bottom