Texas Instruments TI-2500 / Datamath Pre-Series (First Run)

Date of introduction:  never Display technology:  LED modules
New price:   Display size:  8
Size:  5.5" x 3.0" x 1.7"
 139 x 76 x 42 mm3
Weight:  11.4 ounces, 322 grams Serial No:  D0000-00080
Batteries:  6*AA NiCd (internal) Date of manufacture:  wk 18 year 1972
AC-Adapter:  AC9100 Origin of manufacture:  USA
Precision:   Integrated circuits:  TMS0110
Program steps:   Courtesy of:  Joerg Woerner

The famous TI-2500 Datamath calculator was first announced in April 1972 with a suggested retail price (SRP) of $149.95. 

The first batch of the injected molded housings was produced in a white color similar to the original design presented by the industrial designer Fred M. Gore of Fred Gore & Associates, Inc. a few weeks earlier.

Beginning June 1972 first customers in selected areas (Dallas and Houston, Texas) received their calculators - still in the white colored housing - before the formally introduction on September 21, 1972.

Don't miss the rare TI-2500 Datamath First-Series and a later TI-2500 Datamath Pre-Series.

In a direct comparison with the later models in the Datamath line, this one uses 6 rechargeable NiCd batteries under the hood. Interesting to see in the battery compartment of this Pre-Series calculator the unpopulated positions of the battery contacts used with the Texas Instruments Minimath Prototype.

Dismantling this early TI-2500 Pre-Series calculator manufactured between end of April and early of May 1972 by Texas Instruments reveals almost no differences to the First Series products. You'll notice already the CE/D-key on the upper left of the calculator, this key recalls the display. To reduce power consumption the electronics of this calculator will shut down most part of the display after few seconds of non use.

The electronics is centered around a TMS0111 single-chip calculator circuit, a variation of the original TMS0100 design. Read more about Texas Instruments' "Calculator-on-a-Chip".

We located the featured calculator with Serial No D0000-00080 in February 2019 and almost 47 (!) years after manufacturing it still works like a charm and firing up all segments of the LED display.

A more detailed comparison between the ten known Datamath Versions could be found here.

If you like to determine the age of your Datamath Version 1, follow this link

The TI-2500 was mentioned in TI's press release dated August 15, 2002 to celebrate the 35th anniversary of its invention of the electronic calculator.

Datamath™ is a trademark of Texas Instruments.

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© Joerg Woerner, February 23, 2019. No reprints without written permission.