Plus & Sumlock Mechanical Calculators
PLUS 509/D

PLUS 509

Plus model 509/D

Decimal adder.

This has a direct action keyboard calculator of the "comptometer" type.

It is a model 509/D where the 5 denotes the abbreviated keyboard (keys up to 5), the 09 denotes the 9 columns of keys, and the D denotes a Decimal version.

235 x 182 x 120 mm (9.25" x 7.2" x 4.75").

The machine illustrated has serial number 509/D/892604.

Made in or after 1966, when Sumlock Anita Electronics was formed to manufacture the electronic and mechanical calculators.


The label showing that this is a later machine, made when the manufacturing company was known as Sumlock Anita Electronics Ltd.

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Text & photographs copyright © 2002 - 2017 Nigel Tout, except where noted otherwise.