Terminated: unknown
Practically identical to the TI-25 and identical to the TI-35 II. It has the same peculiarities as the TI-25 (see the page on the TI-25).
This one has constant memory.
The problem with this calculator was that after using this calculator for a while the keys would start to bounce. This was a problem with a lot of the TI calculators of similar design, before the invention of rubber key switches. The battery compartment of this calculator isn’t very practical either, and the flexprint under which the two batteries reside breaks easily rendering the calculator useless.
Shown above are the three versions of this calculator in my collection. The one with the black keys was introduced in 1979, the gold one in 1980 and the one with the silver-look and the blue striping was introduced in 1982.