Texas TI-34 solar scientific calculator from 1987

[jebem]

Recently I have acquired a bunch of old used machines in a local flea market.

This model is a nice calculator powered by a single power source based on a four elements solar panel.
This one was made in 1987, November.

This machine was heavily used and abused, showing dents and marks all over the place, and heavy paint worn on the metallic front panel.
It was even opened and the PCB removed by destroying the plastic rivets and later fixed back with cyanolit glue that have also stuck the keyboard membrane to the PCB because the glue leaked thru the PCB holes.

But it still works fine after all these years and misuse.
I have dismantled it and reassembled it with success as well.
However I didn't fix the plastic rivets for now, because the back cover have several points of contact with the PCB, forcing it to be in place against the keyboard.




Forensics result (9 sin cos tan atan acos asin): 8.999998637




Switching to Mode Hex: NOT(FFFF) = FFFFFF0000
Switching back to Mode Dec = -65536




Back cover label:
Texas Instruments
I-1187
Assembled in Taiwan
R.O.C