After sitting for a few years and my retirement, I decided to get back my high speed. Started it up, got "Adjustment Failure" on the display, so switched out the batteries, no change. (there is no corrosion) I could adjust everything with the buttons and get up and running, with a few issues.

Just as a side note, I had some repair work done on the board a few years back, by a guy in Florida (I think) He worked for NASA and did this on the side.

So now I need to fix my issues. Did the following:
1. Replaced all the fuses, just to insure they were right sized
2. Replaced resistors Q75 & Q77
3. Replaced transistors Q74 & Q76
4. Replaced 7402 chips at U45 & U50
5. Unsoldered U25, replaced with a socket
6. Installed NVRAM6116 in U25 socket, bought from Pinitech

On#5 above, I checked each pin making sure there was no continuity to the next pin.

Turned it on the got all 8s on the display, popped open the back and had a #1 error on the LED, U25 Failure.
Reseated the NVRAM6116, tried again.

Soon as I turn on to I get an immediate error on the MPU LED #6, (could be a 9, but this is a first version of a system 11 board. So should LED should only have 6 codes.

Problem now is i find no reference to an error 6 on a System 11- Nothing board.

I am out of ideas and am super frustrated.

Somebody have idea. I will admit to being a NOOB with it comes to electronics, but I can sure follow directions.

Thanks in advance

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Edit to post I pulled out the NVRAM from the u25, flipped on the game and got error 1. Which it should. Went to reinstall the and noticed pin 24 had broke off. So that may be the major issue. Maybe

Doesn't look like this will be running by Christmas