Monitor only shows a single line in the middle

ArcadeRu

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So everything was working fine today. I decided to plug in a different PCB (pandora) into my dedicated cabinet.

Turned it on, heard pop pop pop and smelled some smoke. Screen is black and only shows a single line in the middle. Switched back to original PCB and same thing black single line in the middle that is showing what's suppose to be on the screen but collapsed to a single line. Tried moving pots, but nothing.

Anyone know what this can be? Am I screwed? Is there a reason this would happen from just switching PCBs?

Edit: Additional info: Chassis is a K7000
 
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Depending on the direction of the line, what you're describing sounds like either Vertical or Horizontal Collapse.

If you know your way around a monitor, I would suggest taking the chassis off, searching for the blown part (most likely a capacitor by your description and especially if the monitor is still using the original caps), and replacing it. If it is a cap, you may want to order a cap kit and replace all of them while you have the chassis out.

As for why it happened when you put the Pandora's box in there, I'm not sure… someone more experienced than me would know better. Feel free to correct me if I'm wrong. I would assume the cabinet you're referring to is using a standard JAMMA harness?
 
I believe it's a standard jamma harness. It's connected to a CPS2 PCB

Thanks I happened to order a cap kit because the vertical was rolling over, wonder if that just gave and the timing was just a coincidence.
 
It's certainly possible. Monitors always seem to die at the worst times. Had a flyback crack on me at an expo when the game had been running fine for weeks before. Give an update when you get the kit put in! 👍
 
What chassis is it? I think it's more likely a transistor rather than a cap. If it's a g07 I would suspect these
 
Also side note, just measured my power supply, it's outputing 13.4 volts on the 12v, is this within spec?
 
Anytime you change anything or move them, all is fair in love and war.
Notably any older games with fabric wires.

Plug them in, see which fuse blows - follow the magic smoke / char to find the problem hopefully.
 
it's an unregulated voltage. it's within tolerance.

is it a horizontal line (vertical collapse) or vertical line (horizontal collapse) because they're entire different components.
There is a line going horizontally in the middle of the screen.
 
Thanks. Any ideas on how I can fix a vertical collapse?
yes, the parts in the red box are what carry the +24V to the vertical IC (whichever type you have installed)

R91 is a fusible resistor, meaning if a short condition is present on the +24V line, it will go open. I've never had a vertical IC be bad, it's usually D13 shorted and made R91 go open. you need to test these parts in this circuit. if R91 is open that means there's no +24V to power vertical deflection.
 
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