Texas Instruments SR-52

The TI SR-52, introduced in September 1975, was a programmable scientific calculator featuring a magnetic card reader for storing and retrieving programs. It utilized Texas Instruments' Algebraic Operating System (AOS), allowing users to enter complex equations more intuitively. Powered by a TMC0501 arithmetic chip, the SR-52 offered 224 program steps, 20 memory registers, and a 10-digit LED display. It was designed to compete with the HP-65, offering advanced programmability for engineers and scientists. The calculator was bundled with a thermal printer (PC-100) for output capabilities and retailed for $395, making it a premium device at the time. The SR-52 was succeeded by the TI-59.

The "SR" in Texas Instruments calculators stands for "Slide Rule"2. TI used this designation for its early scientific calculators, such as the SR-50 and SR-52, to emphasize their ability to perform advanced mathematical functions that traditionally required a slide rule. This branding helped position TI’s calculators as powerful tools for engineers and scientists transitioning from manual calculations to electronic computation.