NBA jam help!

theyangman

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So I just had my machine on that I'm fixing and I was adjusting the colors on my monitor. I turned it off for a second and when I turned it back on, I get nothing!

My PCB doesn't light up anymore so I quickly swapped in my spare board and nothing.

My monitor is still getting power, cause when I turn the machine off I get the CRT to blip and I can see it turning off.

What should I check? I didn't touch anything inside the cab!

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Yes, silly newbies...

I obviously have a voltmeter. But it's not one of those power supplies that are readily labeled. It looks more like a PC power supply....

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Peter Chous in my experience are notorious for this. they have fans that seize up frequently and another flaw in that the +5 adjustment pot somehow gets dirty enough to trip the overcurrent protection on the power supply. disconnecting the JAMMA harness and wiping the pot with the power off, then powering on and adjusting the voltage to a safe point (for T-unit boards such as this, 5.20V is a good place to start), then powering down, reconnecting the JAMMA harness, and powering on again -- the game should work.

the PSU guide in my signature details everything you would need to do, but that unit is over 20 years old now, you'd do best by replacing it like Broodwich says.
 
Peter Chous in my experience are notorious for this. they have fans that seize up frequently and another flaw in that the +5 adjustment pot somehow gets dirty enough to trip the overcurrent protection on the power supply. disconnecting the JAMMA harness and wiping the pot with the power off, then powering on and adjusting the voltage to a safe point (for T-unit boards such as this, 5.20V is a good place to start), then powering down, reconnecting the JAMMA harness, and powering on again -- the game should work.

the PSU guide in my signature details everything you would need to do, but that unit is over 20 years old now, you'd do best by replacing it like Broodwich says.
OK, ordered the ps off eBay. But here is my next question.

How do I wire up a screw down ps to this for a temp fix?

I got one lying around and I'm so close to finishing this NBA jam restoration and I don't want to wait another week and a half or two weeks for this thing to arrive here. I'm assuming I can just match up the ground, 5v and the 12v, to the appropriate terminals. But how do I get power to this?

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You can make a small harness that has the terminal connectors that can terminate to a match to the connection you have for the kick harness wiring.
Doesn't need to be that long.

OK, ordered the ps off eBay. But here is my next question.

How do I wire up a screw down ps to this for a temp fix?

I got one lying around and I'm so close to finishing this NBA jam restoration and I don't want to wait another week and a half or two weeks for this thing to arrive here. I'm assuming I can just match up the ground, 5v and the 12v, to the appropriate terminals. But how do I get power to this?

Sent from my Pixel XXXL
 
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