Galaga Midway - Pulsing 5v and GND

Galactimus

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Edmond, Oklahoma
I have a Midway Galaga PCB set that plays completely fine. However you can see noise in the graphics and the image jumps. I have found that the Video PCBs +5v and ground are both pulsing like they have a signal on them. I have looked at everything I can think of and can't for the life of me find what is going on. Any guidance or ideas are greatly appreciated.
 
Did you measure the AC ripple on your DC bus? Was this by a multi-meter or oscilloscope?
 
I see the pulse with a logic probe and found it when looking for another issue. Interestingly, when I connect the ground lead of the oscilloscope, the pulse goes away and the image stabilizes.
 
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