That was it!
Pin E was being used to power my coin slots and not -5v. I gave pin E -5v and the switcher is up and running!!
I have a mess to clean up and a lot of work ahead to make it look nice now. Need to get my coin slots lite up again as well. Thanks guys!!
Thanks again. Sorry to be such a total noob with this.
I don’t see anything misaligned or flawed with the jamma harness. I’ll keep looking though. I measured the pins again at the jamma harness. Should pin E (-5v) read 0 if no pcb is connected?? Actually, that pin is a thin yellow wire...
OK! This is crazy!
Measuring at the end of the jamma harness I get:
Pin 3 & 4: Just over +5v
Pin 5: -5v
Pin 6: 11.33-11.67v
NOW, as soon as I plug the jamma harness into the 6-1 switcher my power supply shuts down. Barely any voltage across the pins.
If I very slowly plug the jamma...
Makes sense. Thanks again. I’ll check as soon as I can.
I did buy a new happ 15amp switching power supply but didn’t want to install it in fear of creating more issues.
Would something like this PS be better since it’s almost plug and play...
Thanks guys.
I won’t be able to validate with a multi-meter until tomorrow night.
I tried the switcher in my converted jamma cabinet and it works just fine. The one it works in is a midway converted MK 3 that now runs a Coinops 8 Xbox. Power supply is a Powermaster111 150w 10amp.
It’s the...
I patched in a +12v to pin 6 (F). No luck.
I traced the small red +5vdc pin 4 (D) back to my coin counter. I took that and temporarily patched in a +5vdc from pin 3 to pin 4 but there’s no change with that either.
All the ground wires look good. I did see pin E and 27 (smaller grounds) trace...
The pic above is of my actual jamma harness. I was trying to show top pin 6 12v orange missing.
I have a molex connector for the harness on the power supply but I do not have a push in terminal for the jamma harness. I wish radio shack still existed!
Yes, I do have spare molex pins!
Perhaps it’s my power supply but the switcher refuses to run without that wire on the jamma harness. In my other cabinet that pin is wired and the switcher powered right up.
Again, this has been 2+ years in the making. When I originally tried to get this up...
^Thanks.
I found it strange my original MK4 jamma harness was/is missing this pin. In order to make my 6-1 switcher power up I need this pin. So I can simply (properly) splice a 12v wire from the power supply harness and into the top pin 6?
Hi guys, I’m hoping someone can assist me with a MK jamma harness. I have an original MK 4 arcade that has functioned perfectly for many years. Over time, I purchased every Mortal Kombat pcb and used each one without a switcher inside the MK4 cabinet. Two years ago I learned how convenient a...