ti sr-50

texas instruments first complete scientific calculator introduced early 1974 for $169.95.

this model was superseded by the sr50a and later the sr50-II. the sr50a is said to have been improved in accuracy, although the original does pretty well nevertheless. like a lot of ti machines, it operates internally to 13 digits. this gives it a significant edge over most others and significantly more accurate than the hp35 with which it was to compete at the time. the competition for scientific models continued to intensify quickly bringing prices down.

ti were adept at producing cost effective and popular models. hewlett packard were the leaders at the high end, but not everyone could afford their models. later models like the ti-30 brought the cost of a scientific calculator into everyone's price range.