I used the ram viewer to look at that address space. It looks like the first 4KB of that ram has that one byte stuck… Which is odd because these are 32KB chips and there are two setup to make a 16-bit wide interface wired up as 32Kx16. I wonder if one of the ram chips is *still bad*?

And once I got a JAMMA harness rigged up… Well darn more diagnosing to do. At-least we know for sure now that it definitely has an issue in that battery backed ram. Which is where that ram chip was messed with. Good thing is my repair seems ok after some feeping around with the meter.

Well first side quest was to fix this arcade monitor. This is one of those cheap turn a TV picture tube into an arcade monitor chassis. It uses… very many no-name cap brands. So those needed changed. I left the three biggest ones alone hoping at-least those still worked and they seem to.

With the glue on the board now and the relatively thick wire. I had to get “creative” to make the chip sit right. Well it’s either going to work or I’ll find out something else is wrong with this board. I have to burn a rom then get out an arcade monitor and JAMMA harness and give it a go tomorrow!

It’s not fun or easy. I kinda had to put some glue down under the new “pads” cure that. Hope it holds and tack the wire to the trace. Then clean all that flux up. Rough up the board. And put some more glue down to be sure it all holds well. Multiple times the first glue down didn’t hold great…

Having a binocular microscope helps. Using 30awg wire and flattening it out with flat nose pliers close to the inside of the lever point to get a lot of leverage to flatten it. The one pad near a via is easy. That’ll hold without glue. The other pads/wires I gotta try and UV glue down.

The other models of Sound Canvas I have, SC-88 ST, SC-88 ST Pro, and SC-55 MK II all have through hole caps that look fine. Always good to take things apart to check it out.