Accession No

4529.007A


Brief Description

Cambridge Programmable electronic pocket calculator, by Sinclair, English, 1977 (c)


Origin

England


Maker

Sinclair


Class

calculating; computer technology


Earliest Date

1977


Latest Date

1977


Inscription Date


Material

Plastic


Dimensions

Length 111mm; width 45mm; thickness 22mm


Special Collection

Francis Hookham Collection of Hand Held Electronic Calculators


Provenance

Donated by Francis Hookham in 1987. Francis Hookham acquired this calculator from Sinclair in exchange for a faulty ("erratic[ally] working") copy of the same Sinclair Cambridge Programmable electronic pocket calculator. The original calculator was donated to Francis Hookham by a private individual in 04/1979.


Inscription

“sinclair
Cambridge Programmable” (front, centre left)


Description Notes

Cream Sinclair Cambridge Programmable, with black key panel, black keys and a black on/off switch at the front top right.

8-digit red LED display, with purple background.
Battery cover protrudes around 5mm from the rest of the case on the underside of the calculator, causing it to be very unstable when used. For this reason it was referred to as a ‘pregnant’ model.

Keys are short-travel, heavy to the touch and give a prominent click on depression (S Davis 15/6/2007).


References


Events

Description
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!


FM:41711

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