27 March 2020

Texas Instruments TI-1500

What I found!!
Texas Instruments TI-1500, that's the third calculator I bought at "Barattolo" flea market in Torino. This one was also battery-heavy, with LED display. There were several versions of TI-1500 back in its days, but I think they all share an enclosed rechargeable battery pack. Mine had two Ni-Cd AA that had gone bad. Quite bad, actually.

The leak has spread almost everywhere on the board leaving intact the display (looks good at visual inspection) and probably the keypad (cannot inspected, but the back is clean).

Without batteries.
After removing the batteries I have cleaned the board with white vinaiger and then water. Since the keypad is blocked to the top shell of the calculator, I had to wash it trying to keep water away from it. Also on one side of the top shell the leak had sneaked under the silver coating and water+vinaiger effect broke it from the inside. This is becoming challenging.

I left it dry on the radiator and tried a power up with an external 2.4V power source. Well, the display showed something but no reaction to keypresses.

I've got too many open projects to take properly care of this calculator. It could stay as is, or it could become a sort of numeric display/clock, as usual.