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Sterling Currency Calculators
Contex

Contex Sterling derivative

Contex

This is a low-cost, plastic, Abreviated-Keyboard, machine. The mechanism is derived from that of the Comptometer, but with the keyboard and display reversed.

It has four £ decades, a single tens of shillings key, shillings, pence, and 1/4 & 1/2 pence.

To enter a number above 5 the operator has to press two keys in succession in that column which add up to the number required.

To enter 11 in the Pence column the operator has to press 3 keys !!, eg. (5)+(5)+(1).

203 mm x 233 mm x 70 mm. (8" x 9" x 3").

Introduced in the early 1950s it cost £18 12s 6d Sterling (about $50).

Another model was available without the 1/4 and 1/2 keys but with an extra column of £ keys on the left.

Made in Denmark, distributed in UK. by Office Machinery Ltd. (Omal).

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Sterling Calculators

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Abbreviated Keyboard
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Contex
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© Text & photographs copyright Nigel Tout  2000-2008 except where noted otherwise.