Accession No


Brief Description

Texas Instruments Datamath TI-2500 electronic pocket calculator, 1972 (c).


Great Britain


Texas Instruments


calculating; computer technology

Earliest Date

Jan. 1, 1972

Latest Date


Inscription Date




Length 138mm; width 71mm; thickness 42mm

Special Collection

Francis Hookham Collection of Hand Held Electronic Calculators


Donated by Francis Hookham in 1987. Donated to Francis Hookham by a private individual in 1979.


“Datamath” (front, centre right)
[Texas Instruments Logo] (front, centre left)

Description Notes

Cream and black Texas Instruments Datamath TI-2500 (2nd version), with black key panel, cream number keys, olive function keys and an orange ‘equals’ key. A black switch at front top right changes the decimal display between chain and constant, and a black on/off switch is on the left-hand side.

8-digit red LED display.
Operating instructions on sticker on rear.

Keys are short-travel, well weighted, and give a bright click upon depression (S Davis 19/6/2007).

Fair condition.
Keyboard scratched and rear panel sticker peeling off.


Mikey McGovern; 'A brief history of calculating devices'; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge:


Pocket Electronic Calculator

The pocket electronic calculator is now familiar to us all. However, these everyday objects were still a novelty in the early 1970s and priced out of the reach of most customers. To our modern eyes, the operation of a calculator is quite simple, at least for basic arithmetic. We just push the buttons and the machine does the hard part for us. Since calculators never make mistakes, we need never worry about what goes on inside.

Behind the buttons and screen lies a complex set of miniature circuits. It is the ability of electronics firms to make smaller and smaller components that has led to the success of the calculator. All the electronic circuits that provide the calculating power can now fit onto tiny ‘chips’ of silicon. By also developing the technology for liquid crystal displays (LCD’s), manufacturers were able to shrink calculators even further. When solar power arrived towards the end of the 1970s they could even be made without batteries. Prices fell whilst popularity soared.

Despite all this technology, successful use of the calculator still relies on the knowledge of the operator. The latest machines pack in countless functions and require a large instruction manual. Their increasing power has led to debates about their proper use in schools. The widespread use of calculators – at school, home and in the office – has been blamed for falling standards of arithmetic.

This is in contrast with the early days of calculator use. During the 1970s, a number of textbooks were published to encourage people to use what was still an unfamiliar instrument. These would give examples of how calculators could help with anything, from income tax forms to the weekly shopping list!


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