Ok, so I've got two broken HP-22s. One just doesn't power up, due to what appears to be damage to the etches on the PC board from battery corrosion. The other powers up, but half its ram is bad - stack and basic 4-functions work, but any use of the storage registers (which means, any use of the financial functions) result in stuck bits an poor calculations.
I'm thinking it might be possible to build one working 22 out of these pieces. Seems like the simplest notion would be to transfer the chip containing the register RAM from the etch damaged unit to the RAM damaged unit, but that could just be naive on my part. The big thing stopping me from doing this is that I don't really know which chip is which.
Suggestions?