Need repair tips... please?

[goatdan]

Considering how I usually can fix these things without reading how to do it or whatever, I feel kind of goofy asking this but...

 

Both of my machines seem to be having problems suddenly. I have a Bad Dudes cabinent that I got for $5.00. It actually isn't "suddenly" having problems, it is just that I'm finally getting around to fixing it up and now it has me baffled. When I got it, it was supposedly a 'dead' machine. The only thing dead about it was that someone had unhooked the power supply, which had fritzed.

 

I replaced the power supply with another one that worked in the last machine I had it in, and I can now get everything to work with the exception of the monitor. I had the monitor working on my other game, although not perfectly. All the wiring appears to be perfect. Any ideas?

 

My other game suddenly decided to have a strange problem too. It is Ajax, another JAMMA game. Upon powering up, the game acts as normally during attract. As soon as the actual gameplay starts, the game quickly flips through the first two seconds of the start of the first four levels and then resets. Any ideas? I'm out

[Arcadenut]

I replaced the power supply with another one that worked in the last machine I had it in, and I can now get everything to work with the exception of the monitor.  I had the monitor working on my other game, although not perfectly.  All the wiring appears to be perfect.  Any ideas?

 

Please be a little more specific.

Do you get a picture at all?

Do you hear the high voltage whine?

Does the neck of the tube glow?

 

What brand of monitor is it?

How old is it?

 

Chances are, it needs a Cap Kit. Those are fairly easy to do (although Dangerous).

 

 

My other game suddenly decided to have a strange problem too.  It is Ajax, another JAMMA game.  Upon powering up, the game acts as normally during attract.  As soon as the actual gameplay starts, the game quickly flips through the first two seconds of the start of the first four levels and then resets.  Any ideas?  I'm out  

 

Sounds like a board problem. Try reseating any socketed chips. You may also want to check the voltages coming from the PS. They should be fairly close to spec (+5, -5, +12). If they are off a little, it shouldn't matter (+-.2 Volts is probably acceptable for most games).

 

Some games have what is called a "Watchdog Circut" which monitors the board and if it finds a problem resets it. Your best bet is to test your cabinet with another JAMMA board. If that board works fine, then you know its a board problem and you can look for a new board.

 

If the other board doesn't work in that cabinet then you know you have a cabinet problem.