Help deconverting a pacman board from jamma

2PacMan

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Bought a pacman board, when it arrived I see it was modified to work with a jamma adapter. I'm trying to get it back to original. My board has the diodes cut at D8, D7, D3, and D4. There's also a jumper wire in the upper left side where the large ceramic diode is. If I resolder those diodes back in and cut that jumper, is that all I need to do to get the board original again?

I know those diodes convert AC to DC, so I'm worried I might fry the board if I don't do this just right.
 
The question might be why was that done in the first place? Pacman boards will run on DC with a JAMMA adapter with no modifications. This board may have had problems with the rectifying circuit which precipitated this mod.
 
The question might be why was that done in the first place? Pacman boards will run on DC with a JAMMA adapter with no modifications. This board may have had problems with the rectifying circuit which precipitated this mod.

That is a good question, I don't know the answer. Would it do any harm to try to convert it back and if it doesn't work, then I'd know it's something with the rectifying circuit? I just don't want to fry anything important.
 
I am the previous owner of this board and just tested it out my bench with a jamma adapter and it worked fine. My guess is the original owner probably used a switcher with the boards since there was a couple of wires soldered on with spade connectors.
 
Here are a couple photos I took of it....
 

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Yeah, I'd resolder the diodes in and remove the jumper and try it.

As others have mentioned, if it was done because the power section was broke, you may need to fix it. The 5v regulator sometimes dies.
 
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