TI Prototype Calculators




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	TI Prototype and Preproduction Models Found!

New TI Find - a LCD version of the Datamath!!!

We have information and photos of a calculator which was only rumored to exist. The Minimath is a Datamath's (TI-2500) visual twin. The boxy, yet stylishly smooth, case looks the Datamath. But the difference is the color (white instead of beige), the display is LCD, and the top has a cutout with a clear "window" to help light the LCD.
We have two photos of the Minimath. The first is an overall shot from above. The second photo shows a closeup of the LCD display from the side.
This calculator was produced in mid to late 1972 as a companion to the Datamath and used the LCD display to reduce the power requirement of TI's first calculator product. However, production problems with the LCD display (then a new and unrefined electronic product) could not be resolved. Production of the Minimath was halted.
At this time, only one is known to exist, but there may be a few more lost in desk drawers of some TI engineers and production people.
Extra detail: This may not be clear in the photos but above the chain/constant switch on the keypad area, "Minimath" is "engraved" into the black trim of the case and the letters are gold colored.
Thanks to CB Wilson for his help in obtaining the information and these photos for us.

Texas Instruments Prototype and Preproduction Calculators

In November 1998, several clear-cased TI calculators went up for sale on the ebay internet auction site. I contacted the seller, Raymond Flowers (quadrajet1@aol.com) to find out a bit more of the background behind the calculators and the sales.

Raymond purchased a variety of calculators from a TI engineer who was involved in the beginning of many of TI's earliest models. The calculators were early engineering models and preproduction units that the engineer had the foresight to save from the trash pile.

The calculators included the some models in a clear case to see how everything fit together (like the SR10, SR11, and SR50). In a few instances, the models were prototypes that never were produced (like the Exactra 100 and Minimath LCD). The other photos show glimpses of early pre-production models. Raymond was kind enough to give me permission to post his photos of the calculators. This is a great behind-the-scenes snapshot of TI's early design efforts.

My appreciation to Raymond for sharing these photos with us!

Please note that the links to these photographs should be restored shortly.

Minimath LCD (never produced for sale)
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Exactra 100 (never produced for sale under that name)
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SR10 (clear-case)
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SR11 (clear-case)
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SR50 (clear-case)
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View 4 (a second, non-clear-case model)
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SR16 (pre-production detail pictures of the keypads)
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Exactra 21 (pre-production)
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Montgomery Wards P300 (pre-production model for the large catalog/department store)
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Datamath, TI-2500 (pre or early production models)
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