Bohn Contex 10  
Written by Accutron on 2017-03-01  

The Bohn Contex 10 is a portable 10-key mechanical calculator, manufactured by Brdr. Carlsen A/S in Birkerod, Denmark. When a number is entered on the keypad of the Contex 10, a pusher extends one of a series of pins from the front of the keypad assembly. A row of sensing levers is positioned in front of the pins. When the adding bar is depressed, the sensing levers pivot downward across the pins, stopping when they contact an extended pin. The opposite ends of each lever have a toothed face, which meshes with the result register.

The Contex 10 was a widely adopted adding machine. As of 1962, Bohn was advertising the $125.00 Contex 10 as a "portable computer", emphasizing its small size and weight, and its suitability for use while traveling. Bohn also offered a motorized Contex for $235.00.


Bohn Contex 10 portable mechanical adding machine.


Contex 10, underside instruction placard.

This article is part of the [Mechanical Calculators] exhibit.

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