Could use some assistance with Midway NBA Jam PCB with Shogun Supergun and Jamma PSU General questions

[sLpFhaWK]

Hi there, I bought an NBA Jam PCB, and today I was able to pick up locally a MVS Single Slot which isn't relevant to this post, but it came with a Retrotink 2x Scart display adapter with a scart cable, a Retro Arcade us 16a Jamma PSU, and a Shogun Supergun.

The website says the Shogun Supergun works on all Jamma PCBs, but when I tested it there, it didn't. I know the board works because I pulled it from the cab it came from right before I left, but then I noticed later that it didn't have the -5v line connected. According to my Google-fu, it's needed for the audio board and possibly some other functions on the main board. I am not familiar with Midway PCBs at all, but I was hoping it would work.

Can I get confirmation from someone who knows? I am in the process of getting that -5v line connected but would like to know for science before I do it.

Thanks!

 

[sLpFhaWK]

I couldn't get the display to show on my tv using the retrotink 2x scart, so i used my ossc and it displayed, but it wasn't centered and i had no sound. the volume pot was wired terribly on the sound board so i don't know if thats needed or if its something else. the entire pcb did work in the cab i got it in though, more testing to be had tomorrow.

oh and sadly to add the db15 port with the attached neo geo controller didn't work w/ nba jam. boo

 

[Big_P Big_p]

Check the scart cable first. Some carry audio and video and some only carry rgb video.

And check if there is 5v on the db15 5v pin some controllers require 5v at the pin, while others don't and not all db15 connections have 5v at the pin

 

[sLpFhaWK]

Check the scart cable first. Some carry audio and video and some only carry rgb video.

And check if there is 5v on the db15 5v pin some controllers require 5v at the pin, while others don't and not all db15 connections have 5v at the pin

So everything works as it should when using the mvs both sound video and controls. That was with the retro tink 2x scart though.

 

[Big_P Big_p]

If the cable was delivering audio for the MVS and the controller also worked on the MVS then it is likely a board issue. Do you have photos of the volume pot?

I have only ever had to fix UD7 (74F253) which appears to be a common problem but presents as a series of bad roms at boot and no graphics and UE13 which commonly looses the solder connection on one or more of its legs and can present as a range of symptoms but typically not what you are describing.

I loved the game but don't really know the board well hopefully someone else can point you in the right direction because it's still a blast to play with friends.

 

[sLpFhaWK]

The board worked perfectly fine in the cabinet I pulled it out of. The only reason it got pulled was that the CT crashed on itself, and I couldn't figure out how to fix it. Plus, it was badly water-damaged, so I know the board 100% works.

I will get a picture of the volume pot. The wires were never soldered on to the actual potentiometer; they were just stuck into the connector on the board.

The issue with the picture on my OSSC, I think, is some sort of setting using that. I've had it for a while but never used it, so I don't know what I'm doing.

 

[Nic034]

-5v line is mandatory to have sound working on midway boards (mk2, nba jam, killer instinct..). Otherwise, sound boards (or embedded sound chip) will not work at all and so, no sound will come out. Often, you’ve a working led for sound state on motherboard (like mk2).

Take time to check voltage line and to check cable between sound board and mobo, midway board need stable and amp powered 5v line to work correctly (setup voltage in service mode, 5v or 5.1v work fine)

 

[sLpFhaWK]

-5v line is mandatory to have sound working on midway boards (mk2, nba jam, killer instinct..). Otherwise, sound boards (or embedded sound chip) will not work at all and so, no sound will come out. Often, you’ve a working led for sound state on motherboard (like mk2).

Take time to check voltage line and to check cable between sound board and mobo, midway board need stable and amp powered 5v line to work correctly (setup voltage in service mode, 5v or 5.1v work fine)

-5v is hooked up but will pull out meter and verify