Atlas-Rand, Berkey, & Keystone calculators
A series of similar distinctive calculators was sold under the Atlas-Rand, Berkey, and Keystone names. These solidly built models are unusual in using the Burroughs Panaplex II amber gas-discharge display, normally only found in desktop calculators.
Featured here are some of the models:
Note the slight fault in the display causing the top left segment of each character to light.
This example is faulty.
Berkey Keystone 350
Berkey Keystone 350
Distinctive features: A series of similar distinctive, solidly built, calculators the Burroughs Panaplex II amber gas-discharge display.
Display is 8 digits, amber Panaplex gas-discharge.
4-function %. Note that the Atlas-Rand 240 and Berkey Keystone 350 have a 'Constant' switch.
The 'Decimal' switch has two positions: 'Normal' gives a floating decimal point, and '$' gives a fixed decimal point with two places of decimals suitable for money calculations.
Main integrated circuit - by Rockwell.
6v (4x AA batteries).
78 x 133 x 44 mm. (5.7" x 8.5" x 2.75").
Made in U.S.A.
All of these calculators have identical labels on the back, marked "Keystone, Paramus, New Jersey".
Company was founded in 1919 as a toy manufacturer. By the mid-30s it had started manufacturing cameras, and by 1945 was producing a range of movie cameras and projectors and was phasing out of the toy business. The company continued to be very innovative in photographic equipment and in other consumer goods.
In 1965 Keystone was purchased by Berkey Photo Inc., which owned the Omega trade mark.
Addmaster Corporation marketed a range of calculator, from 'Addiator' types and mechanical adding machines to desktop electronic calculators. We have no information about the name Atlas-Rand.
Inside the Keystone 88, showing the Panaplex display and the large number of discrete components.
Inside the Berkey Keystone 350. The circuit board is similar to that of the Keystone 88, with the large black Rockwell integrated circuit (here date coded to late 1972).
The use of a Burroughs Panaplex gas-discharge display in a hand-held calculator was not common. The digits are much larger than contempory LED (Light-Emitting Diode) displays and much more easily readable, as can be seen in the photographs.
However, unlike the LED, this display requires a high voltage to be generated for operation, and there is a warning on the back about the high voltages inside.
© Text & photographs copyright Nigel Tout 2000-2021 except where noted otherwise.