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tsi speechModel: TSI speech+
Battery:  4 x ni-cd

Adapter: 9 vac
Year: 1976
Chip:  TMC1007NL

tsi speech 01 tsi speech 02

 

Info: TSI Speech + with Texas Instruments chip the TMC1007. In the early 1970s, Telesensory Systems Inc. Speech + was the first portable talking calculator for the blind, an interesting point is that, to aid the blind in use, the numbers on the keyboard are in the same order as a phone (with 1 at the top) instead of in the normal order of a calculator (with 9 at the top).

 
with permission of the author www.vintagecalculators.com