Bally MPU Corrosion Repair - question on replacing a 390pf with at 430pf ceramic cap

Bullwinkle

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Bally MPU Corrosion Repair - question on replacing a 390pf with at 430pf ceramic cap

I'm working on my first Bally MPU for an Evel Knievel. I'm following the guide at pinrepair no problem. There was a bit of typical battery corrosion so I ordered the battery corrosion repair kit from GPE.

As the title states, I'm replacing a ton of corroded parts but there are more than what is in the kit so I picked up the rest locally... essentially any component that has any corrosion at all is getting replaced. Which leads me to 8 ceramic caps on the lower right hand part of the MPU board. The values are 390pf. I typically can get most of my stuff locally and stopped into the distributor today but they did not have this value but suggested I replace it with a 430pf ceramic cap.

Is this a suitable replacement for these caps? 4 of the 8 will need to be replaced (the bank of 4 that are closest to the bottom of the board).

Thanks.

-tom
 
I can't see 40pf of difference in a switch return line causing anything bad to happen. I've often swapped the 390's with the 470's used elsewhere on the board, and never noticed anything change in game play. Not the right part, but one that should work just fine.
 
I can't see 40pf of difference in a switch return line causing anything bad to happen. I've often swapped the 390's with the 470's used elsewhere on the board, and never noticed anything change in game play. Not the right part, but one that should work just fine.

Cool..thanks. These components are right on the edge of the corroded area and the bottom most legs show a little green on them, so I really want to get rid of them.

Will give it a go.

Thanks again,

-tom
 
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