Mortal Kombat help PLEASE, I BEG OF U

Im about to lose my mind over this PCB.... here are the facts so far
(This is being plugged into a 4-slot stereo MVS cab)


1. Have MK-1 PCB - loads up and plays game on screen, looks great

2. Have MK-1 Sound board with one ribbon cable connecting it to the main PCB

3. All ROM chips load (turn green) in boot up diagnostic screen

4. Kick Harness works fine, all buttons work

5. Im getting no sound what so ever, not even a pop or crackle

6. Ordered an MVS to standard Jamma coverter from "JammaBoards.com"

7. Even with the converter board I get no sound at all

8. I did opt fo the extra stereo output on the converter but have not had the time to get stereo plugs to solder to the wires it comes with

9. Both PCBs were bought from a guy on ebay that I have used multiple times with no issues, so I tend to trust that its a working setup


Im dying to play this game, anyone have anything to try or know of something Im missing or forgetting possibly?

Help me my neo-freaks , I need ya!!!

If you tried the board before you got the Jamma converter, your amp could have gotten broken.

Did you try it before you got the converter?

Sounds like your missing the power cable and the sound pot. Both of which seem to never come included in auctions.

is it a big red? original mvs?

you probably dont have -5v.

check the edge with a multimeter to see. but im pretty sure the original psu's in big reds dont have -5v.

also i dont know about mk, but i know mk2 has a data/ribbon cable AND a separate power/audio out harness.

I did try it before I got the convertor... I didnt notice anything get hot so I figured it didnt hurt it...

It is a big red cab, all original, its the 4-slot with the two stereo speakers on top...

For the MK board ,I only have the one ribbon cable that connects the two boards togehter... I havent been able to locate any kind of audio knob or pot.

I tried the convertor on an old Double dragon game afterward to test it out... I think something may be up with the convertor now..

I have sound on the double dragion board with it...but just barely...and its accomanied by a high pitch hum of sorts...which changes pitch and loudness when I physically apply pressure on the converter with my hand. Maybe the people at Jammaboards sent me the wrong part? The description of the part talked about how it converts stereo to mono..and the extra plug I paid for does the reverse.

does anyone know a web site that shows a complete MK-1 setup? Im having a horrible time finding info on this game for some reason... I also was wondering if I could figure something out if I had a dip switch guide for the main board

thanks to all who replied

Konig said:

does anyone know a web site that shows a complete MK-1 setup? Im having a horrible time finding info on this game for some reason... I also was wondering if I could figure something out if I had a dip switch guide for the main board

Click to expand...

Here's an online manual that covers Mortal Kombat

so theres:

a 3 wire harness for the volume pot
an 8 pin connector on the mobo to a 6 and 4 pin connector on the sound board, for sound and power. looks like it doesnt use -5v.
and then the ribbon cable.

i got my mk2 harness from these guys:
http://jammaparts.com/Customsound.htm

but the connectors are probably standard molex kk or similar, which are easy to find and you could make your own.

Make sure you know what version you have as well. Theres a T-Unit version and a Y-Unit version. The power cables are different.

The Mortal Kombat games do need -5v, do you have this in your cab or are you still using the original PSU?

Hewitson said:

The Mortal Kombat games do need -5v, do you have this in your cab or are you still using the original PSU?

Click to expand...

You are correct. This is from the Mortal Kombat manual:

Be sure the power supply from your old game is capable of +5 dc at 5A, -5 dc at 2A and +12V at 1A. These operating voltages are necessary...

Click to expand...

its weird that the sound board itself doesnt use -5. (according to the manual...unless im missing it.)

i guess the amp is on the mobo?

I'm pretty sure its an original power supply, but it almost impossible for me to get to it...I have multiple spinal injuries and cant move that machine what so ever.

When you say -5v.. what the hell does that even mean? Hooking it up back-wards?
I have never heard of negative voltage unless the positive and negative are swapped and the power supply allows for it without tripping off.

I must be missing the sound pot, and power cable for it.... I love how people just "happen to" leave out stuff like this when selling something... this guy is not getting any more of my business thats for sure, what a dirtbag...and after years of buying from him he does this crap to me?

Thanks for the links...now I have to figure out if this is worth it... I'm already leaning toward no... I should just get a copy of MK-deception deluxe or whatever its called and play it on my big screen... I heard that MK1 is part of that set...as much as it pains me to get this far and quit

Thanks again for the help guys, even though I'm pissed about the situation I appreciate the help from everyone