Found these inside a non-working 71B

[Dave Frederickson]

(03-17-2018 03:32 AM)MikeSD Wrote:  Here is the FORTH Assembler Module. I can't see anything out of the ordinary. Wonder if there was some jumper that was present that got removed when this was cleaned up.

Anyway, when 1-7, 8 and 13 are used, the system won't power up. I'll be checking voltages tomorrow.

I believe Raymond made this observation, there's battery corrosion residue on the module. That needs to be removed with a vinegar solution or DeoxIT D100 (red). Check for any shorts between the pins with a meter. Also, its possible that the corrosion may have spread under the encapsulation and this is what killed the calc in the first place.

Dave