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.
Board #2 - Bad U13 and U17 Ram chips.
Board #3 - Also bad U13 and U17.
Board #4
Terribly garbled audio due to no -5vdc getting from the edge connector to the sound system.
Thanks again...

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.
Board #2 - Bad U13 and U17 Ram chips.
Board #3 - Also bad U13 and U17.
Board #4
Terribly garbled audio due to no -5vdc getting from the edge connector to the sound system.
Thanks again...
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