What's new

Solmin

Professional
Joined
Aug 20, 2015
Messages
296
Reaction score
178
Location
Houston
I have only one A board. I have a multiCPS2 and ST b boards.
The video comes out but it seems to be missing the red output.
Any suggestions on how to possibly fix this? I'm picking up another A board this week but wondering what is best approach for troubleshooting the a board.

thanks in advance guys!
 
Missing colour could be a bad resistor or a bad logic chip feeding the red line, follow the red line back from the edge connector and see if there's any broken traces and then you'll need a multimeter and logic probe to test further :)
 
I picked up a second A board and it wasn't the a board afterall. Was a loose connection on the monitor side.
System is looking good. Found a new problem though :( Speakers and Q sound not working and no sound out of Jamma. so will deal with that maybe tomorrow.
 

Attachments

  • IMG_3337[1].jpg
    IMG_3337[1].jpg
    869.2 KB · Views: 353
This is happing to one of my cabinets at the moment and I know it's from the wiring also. What wire from your monitor was it? I'm trying to figure this out as I write this.
 
I picked up a second A board and it wasn't the a board afterall. Was a loose connection on the monitor side.
System is looking good. Found a new problem though :( Speakers and Q sound not working and no sound out of Jamma. so will deal with that maybe tomorrow
Do you hear any sound from the test menu sound test?

Do you hear any sound from any other B board attached? If yes, your sound problem is B-board related.

If you do not hear any sound from any B-board then your sound problem might be related with either your A-board, 12v from your power supply or cabinet cabling...
 
The b boards output via RCA to my computer speaker.
I have a ms pacman jamma board which doesn't get any sound via the jamma connector either. I'm thinking it's the cabling from the jamma harness. Will trace it down soon. thanks!
 
The b boards output via RCA to my computer speaker.
I have a ms pacman jamma board which doesn't get any sound via the jamma connector either. I'm thinking it's the cabling from the jamma harness. Will trace it down soon. thanks!
Your sound problem over JAMMA might be harness related, yes.

Btw, the RCA connector is on the A board not on the B boards. Inorder to get sound from the RCA connector, you have to go test menu and enable "Q-Sound". The default setting "might" be Q-Sound anyway, I don't remember exactly...
 
The default sound output is stereo via the RCA connectors, to get sound output from the JAMMA edge you need to go into the service menu, to configuration and then system and change the sound output to mono

Does the Impress have a Q-Sound amp? I thought it was JAMMA only
 
I’m quite positive my CPS2 board outputs audio over the Jamma even if the output setting is Qsound...

Can verify when I get home in 2 weeks...
 
Last edited:
I’m quite positive my CPS2 board outputs audio over the Jamma even if the output setting is Qsound...

Can verify when I get home in 2 weeks...
Mine does with the multi installed but an original does not, no idea why.

....and I've just noticed he is in fact running a multi, I retract my previous statement
 
I’m quite positive my CPS2 board outputs audio over the Jamma even if the output setting is Qsound...

Can verify when I get home in 2 weeks...
Mine does with the multi installed but an original does not, no idea why.

....and I've just noticed he is in fact running a multi, I retract my previous statement
This could also depend on which original B board you have installed I think as the default settings can be different per game
 
Edit: read that wrong

Would be interested to know how that works
 
The Impress does have a Q sound AMP. I also tested with a Ms. PacMan/Galaga board which is JAMMA only and still no sound. will do some continuity testing when I get off work.
 
to answer the thread title, ALL BOARDS ARE WORTH FIXING.
(well maybe not sports games ;) )
 
Well, to fix it or not, CPS2 A boards are good source of parts to fix lots of other boards;

- CPS-A-01 Asic to fix CPS1 A boards
- CPS-B-21 Asic to fix CPS1 C boards
- Lots of RAM to fix various boards
- lots of surface mount logic ICs
- Kick-harness connector to fix soldering iron molested boards
- Connectors to fix other CPS2 A boards with broken pins
- Z80 CPU
- 68K cpu
- etc.

CPS2 A boards are goldmine for a arcade board repairer ;)
 
The worst thing about trying to fix cps2 A-board is how the hell do you get to the components while it's running?!
 
if you have no sound at all, try changing the Z80A
notice the "A", capcom fitted am original Z80 and OVERCLOCKED it.
assholes.
i have seen bubble-bobble pcb's do this too.
 
to answer the thread title, ALL BOARDS ARE WORTH FIXING.
(well maybe not sports games ;) )
Sports games might be able to be converted into something good :P there are some boards that are better off being parted out than fixed though.....


if you have no sound at all, try changing the Z80A
notice the "A", capcom fitted am original Z80 and OVERCLOCKED it.
assholes.
i have seen bubble-bobble pcb's do this too.
They did the same thing on CPS1 and CPS2, SNK did it on MVS boards, a lot of manufacturers did, I'm assuming because Z80s were what they had on hand at the time. To be fair they've lasted a long time being run overclocked so I get why they took the risk
 
Back
Top