Are these two psu boards the same?

Lanky Kong

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This is probably a dumb question but I'm still new to actually repairing machines so here goes anyway.

I popped open the back on my new nonworking Space Zap recently and was expecting to see the bally/midway psu A082-90411-A000 but instead the psu said A082-90411-C000.

It looks identical to the A082-90411-A000 but I wanted to make sure as it had two caps daisey-chained together that had popped installed the opposite way than they should be according to the map I found for the A082-90411-A000.

I've since replaced the two blown caps with a correct single cap with the orientation dictated by the above-mentioned map but it only made a little difference. My marquee now lights up and I get junk on the screen.

I've checked my voltages at the comm motherboard at the bottom of the board cage and they're good except for the -5. For the -5 I am getting positive (+) 5. I'm planning to use the rest of the psu repair kit I got from Bob Roberts but I was just wondering if this issue is tied to a specific spot on my psu.

Anyway, I got off track. Are these two PSU boards the same? I assume they're just different revisions.
 
For the -5 you are getting plus 5? Are your meter leads reversed? If not then many newer machines require -5v to work or the screen is just dark with no picture. Cant use use a switched supply instead? Also most of the time if the screen has garbage its a board issue but not all the time which seems to be your case not your supply. Board needs to be looked into further. Look it over for damaged resistors, caps, etc... I would definitely not use that power supply for now. Try a switched supply if u can next.
 
Well, I rebuilt/repaired my PSU using the kit I got from Bob Roberts and my voltages are now correct. I'm getting 12.36, 5.11, 5.11, and -5.21 respectively. After replacing the -5 voltage regulator my PSU was putting out -5.21 volts on the -5 instead of +5.11 volts.

However, after hooking it up I still get nothing on the screen. It's completely dark. At one point I thought I saw some words flash across the bottom left of the screen but otherwise I get nothing besides a hum from the speakers when I press any button.

I've got an extra complete Gorf boardset w/ cage and an extra WoW boardset w/ cage that I guess I could use to test some of the boards in my Space Zap. Unfortunately, my working Gorf upright is pretty buried behind other games in my storage unit so I am not looking forward to getting it out.
 
Unplug the game board, turn up the monitor brightness and u should see raster on the screen. If not then your monitor is the problem. If the monitor is white with lines this is raster and good then u have a board issue. Try putting it on test mode to check it if u can or swap it with a known good pcb.
 
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