Multiple UMK3 PCB Repair

zenomorp

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Hey guys. I have 2 UMK3 boards that have bad U?? ram and one that's dead. I also have a working board except for the sound. The sound system is not receiving the -5vdc from the edge connector. I have MANY extra boards that I use for parts, so that's not an issue, but I don't have the knowledge or experience to troubleshoot and repair what's causing them to register as bad or if they are in fact bad, how to replace them.

Looking for a tech who can

a) replace the ram chips that register as bad

b) repair the issues that cause them to read bad if it's not the chips themselves.

I can supply all the extra parts. I just need someone to do the diagnosis/labor for me. All the boards are 100% complete. I don't want to simply add them to the parts pile because if it's something easy, such as simply replacing the rams chips, I'd rather get them repaired.

Thanks. I'm still in Afghanistan and won't be home until November, but I'd like to get something set up before hand.

Here are some pics of the boards...

Board #1 - DEAD. Re-seated everything that I could including the roms and nothing. Dead.

SAM_3237.jpg


SAM_3242.jpg


Board #2 - Bad U13 and U17 Ram chips.

SAM_3245.jpg


SAM_3248.jpg


Board #3 - Also bad U13 and U17.

SAM_3251.jpg


SAM_3254.jpg


Board #4

Terribly garbled audio due to no -5vdc getting from the edge connector to the sound system.

Thanks again...

:)
 
Last edited:
Thanks. I'll shoot him a PM.

no prob, i sent a few his way a month or so ago, it takes time but you can't rush perfection.

I was actually thinking about sending you an offer on a couple of those boards but it skipped my mind.
 
I am only interested in having a backup for my MK3 and UMK3 machines, so I need 2 extra working ones. You can have the one remaining non-working one if you want. Just let me know. It'd be easier for me as I'd only have to get 2 of them repaired instead of 3.
 
there's always a chance one won't be able to be repaired. let me know what you decide to do with channel or whomever you decide to go through for a repair (not sure but there might be some other wolf unit repair guy out there). the ram and video errors should be easy fixes for him
 
there's always a chance one won't be able to be repaired. let me know what you decide to do with channel or whomever you decide to go through for a repair (not sure but there might be some other wolf unit repair guy out there). the ram and video errors should be easy fixes for him

Will do. I'll keep you updated on how things turn out.
 
I have a working boardset ill sell you :D
100 shipped

Thanks, but I already have a working extra one. Just looking to get these fixed so I don't have to use them for parts because I already have so many that are used for that.
 
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