Operation Wolf White Screen

[starfighter2]

I'll check that tonight and see if I get anything. I know the 5 volts on the board was low. Tested on all sides to make sure that was at the proper levels.

However, I am leaning towards this being something else since I tested in the game and with a test hardness I made with an extra wire set that I had. I made sure that all the voltages where there before connecting the board. and it has a new power supply. But will look at this tonigh along with the other suggestions and report back what I find.
Thanks

 

[Solder]

Did you check ALL of the voltages on the board itself, ie not just the edge connector?

 

[starfighter2]

I checked both. The edge connector (+5, +12, -5) before I connected the game and then once the game was connected I checked (+5 only) at each corner of the game board via the nearest IC chip.

One thing to note, and don't think it matters but thought I would metion. I currently have the sound board disconnected becuase it sits on top of the game board while I'm testing. This is the only whay I know to be able to test the chips, CPU, RAMs/ROMS on the main board. However, I get the same result no matter if the sound board is attached or not. Let me know if this is not the correct way to test.

 

[Womble]

The lack of sound board shouldnt be a problem, but try running one of the other healthier ones without their soundboard and see if it has any impact.

I cant really offer any advice on what to check next, the loss of video can be a fairly complicated thing to troubleshoot. Heres a Bubble Bobble board I fixed recently with the same fault, it was a simple fix (just 1 chip), but took hours of non-simple troubleshooting to find the simple fix.

http://retrocomputermuseum.co.uk/forum/index.php?topic=3913.0

 

[kb0jjn]

I got one of my many sets working, kin of. I can play shoot and launch grande but have no cab and so cant test gun.

If I can be of any help with reading let me know and I can probe or ohm my board set.

 

[Womble]

Double check that the T0070RGB SIP is not missing from the board. It's a thin black wafer that often gets snapped off so cleanly it's hard to notice anything should have been there. Losing that gives either a black or white screen depending on the board.