
The case is yellow, and it looks like it's full of plant matter as well.

Did somebody drag this through their lawn?

Vintage MX Blacks. I try to like linears, I really do, but they just don't do it for me. I've got new switches on order already, so I'll need to get these out of here, cleaned up, and probably sold off.

Pretty yellow. I'm kicking myself that this image is so blurry. The rear label didn't survive the restoration and I don't have a clear photo of it.

I want to kiss whomever designed this board. They used brass inserts for the case screws, which is such a luxury.

The metal leafsprings are a bit rusty, as are all the screws. They'll get rust removal, and I need to source a couple more screws. (Maybe replace the set)

And here I thought the front of the board was dirty. The back of the PCB was covered in at least two kinds of grime. I've since gone over it with a silicone scrubber and some isopropanol. It's worlds better but not really done yet.

The plate is OK condition, but I think I need to do something about that rust.

I like seeing TI chips in stuff. Am I reading this correctly as the last week of 1984?

The case looks a lot better after a thorough scrub and some retrobrite.

I really tried to lift that label off in one peice, but it disintegrated in my hands. I also got some chalky streaking after the H2O2 treatment, and thought I was effed. But a single coat of satin clear coat seems to erase whatever causes the white splotches. I suspect overtreating with H2O2 causes microscropic surface pitting, which results in the chalky white blotches. Clear coat fills those in.

This is actually a monster image, stitched together from a bunch of macro shots inside photoshop. The file is 750MB. Full size here.

Tracing the PCB is medatative. And I reiterate the nice things I have to say about the board designer. They silkscreened a bunch of useful information onto this thing.
Traces in isolation
Spoiler:
https://docs.google.com/spreadsheets/d/ ... sp=sharing
A full map of the switch matrix for the PCB, with pinouts for the rows and columnS
Just need to wire the right microcontroller in to take over for the TI chip. Lots of desoldering to start with.