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DATAMATH CALCULATOR MUSEUM |
Texas Instruments SR-51 (late model)
| Date of introduction: | January, 1975 | Display technology: | LED modules + lens |
| New price: | $224.95 | Display size: | 10 + 2 |
| Size: | 5.8" x 3.2" x 1.3" | ||
| Weight: | 9 ounces | Serial No: | 53539 |
| Batteries: | BP1 | Date of manufacture: | wk 13 year 1975 |
| AC-Adapter: | AC9200 | Origin of manufacture: | USA |
| Precision: | 13 | Integrated circuits: | TMC0501, TMC0522, TMC0523 |
| Memories: | 3 | ||
| Program steps: | Courtesy of: | Joerg Woerner |

With
the SR-51 Texas Instruments started a series of scientific calculators that
added statistical functions and conversions to the "usual functions".
You'll find similar performance and keyboard layout in the line SR-51 -> SR-51A
-> SR-51-II -> TI-55
-> TI-55-II -> TI-55-III. But none of them was done as perfect as the
SR-51. It was designed to stay decades as the close relative SR-50.
Compared to the previous models the SR-51 got a keyboard design with white, grey,
yellow and orange keys and gave an outlook to later TI calculators.
To reduce manufacturing costs and to give a similar appearence to the SR-52 and SR-56 calculators the SR-51 was replaced within few month with the SR-51A. The calculator on the left was produced March 1975, earlier models used bold letters for the second functions. Compare it here.
The
SR-51 was the first calculator in TI's line using stacked Integrated Circuits (Piggy
Back IC's). Please note on the right picture the two SCOM circuits.
Funny to know, that this calculator works with the PC-100 "Printer Craddle" from the SR-52 and SR-56.
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If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.