USA - 1976

Scientific, Financial
Red Led
"Texas Instruments SR-51-II 4477 USA 2016564. This calculator was historically sandwiched between the SR-51A and the modern TI-55 calculator. It used already the new housing of the TI-55, but instead of the One-Chip, One-PCB solution it used a very complex electronics with stacked IC's and stacked PCB's. Don't underestimate this pretty calculator." Joerg Woerner

Courtesy of: Joerg Woerner

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