Wiring a Pacman board to a switcher

gleegum

Active member

Donor 2018, 2025
Joined
Nov 23, 2018
Messages
156
Reaction score
60
Location
Florida
I recently got this Pac-Man board, supposedly in working condition, but I'm not familiar with this PCB.
I see that the board originally uses a 7V AC transformer, but I've read that it can be powered with 5V DC through an adapter and connected to a JAMMA harness.
So, I built the adapter and connected the board, but I'm only getting a black screen.
When measuring any 74xx chip, I'm only getting 2V instead of 5V.
The power supply is set to maximum, and it measures 6.2V at the edge connector. I also ran 2 (5V + GND) extra thick wires from the PSU to the edge connector.
Is this PSU not sufficient, or am I doing something wrong?

I've attached pictures of the PSU and the adapter.
Thanks in advance.

IMG_20250603_114329547_HDR.jpg
IMG_20250603_114356507_HDR.jpg
 
Or, if you don't like reading... Just buy this adapter and plug it into a JAMMA setup:

Del

That's not all he'd need to do though! From the pcbjunkie product page:

Important: You should convert the game to run on DC voltages before using this adapter. Using these adapters with the original games that run on AC, may not work unless the voltage is increased. Please check my guide on how to convert an original AC board to DC.
 
I have both Mike's Arcade and Arcadeshop adapters, only Mike's works with Galaxian also. the Arcadeshop one I think won't have sound. all the same it'll be fine for Pac-Man.
Looking back at one of my videos (yes, I had to check to make sure, since I also have Arcadeshop's JAMMA adapter as well) I am indeed missing sound when plugged into a JAMMA rig. Could have sworn I had sound at one point? But sure enough, no sound in the video! I stand corrected.

Del
 
Looking back at one of my videos (yes, I had to check to make sure, since I also have Arcadeshop's JAMMA adapter as well) I am indeed missing sound when plugged into a JAMMA rig. Could have sworn I had sound at one point? But sure enough, no sound in the video! I stand corrected.

Del
yes I have both. my Mikes one was in some box that got moved a couple years ago. when I found it I was like ok great. I left the Arcadeshop one at work in case of emergency. lol
 
Back
Top Bottom