Bowmar 905 Handheld Electronic Calculator


The Bowmar Instrument Corporation was established in Fort Wayne, Indiana, in 1951 by Edward A. White, an engineer who had attended Tufts University. The firm came to sell solid-state light emitting diodes, but was unable to persuade Japanese calculator companies to use them in calculator displays. This prompted Bowmar to enter the calculator business in 1971. This is a relatively early Bowmar calculator.

This handheld electronic calculator has a plastic case colored tan and brown with a plastic display window and keys. It has an array of nine digit keys above the zero and decimal bars. Four keys for arithmetic functions are right of these. At the top is a constant switch, a clear entry key, a clear key, and an on/off switch. Behind this is a red eight-digit LED display. A mark at the top reads: BOWMAR.

A plug for a power cord is on the right side. This example lacks a cord.

An "OPERATING OUTLINE" in raised characters on the back of the case gives instructions. A tag at the bottom reads: MODEL 905 Serial (/) NUMBER 118910 (/) BOWMAR/ALI Inc. Acton, Mass. 01720 U.S.A. (/) Made in U.S.A.

Four screws hold the back of the case to the front. Removing these reveals one small and two large circuit boards. A mark inside the case near the top reads: E905-010.The same mark is on the inside bottom of the case. A mark on the upper circuit board reads: D905-300. A space for a battery or battery pack is empty. The calculator has no separate battery compartment.

A different form of the Bowmar 905, with a percentage key rather than a constant switch, was advertised in the Washington Post in 1973. A January 28, 1973 advertisement gives a price of $99.99. The ad, which included several electronic calculators, was entitled "if you're still using your head, you're not using your head."


Robert Metz, "Market Place: Keeping Figures in Your Pockets," New York Times, May 27, 1972, p. 36.

Washington Post, January 28, 1973, p. K10.

Guy Ball and Bruce Flamm, The Complete Collector's Guide to Pocket Calculators, Tustin CA: Wilson/Barnett, 1997, pp. 35–36.

Date Made: 1972

Maker: Bowmar/Ali

Location: Currently not on view

Place Made: United States

See more items in: Medicine and Science: Computers, Computers & Business Machines, Handheld Electronic Calculators


Exhibition Location:

Credit Line: Gift of John B. Priser

Data Source: National Museum of American History

Id Number: 1986.0988.204Catalog Number: 1986.0988.204Accession Number: 1986.0988

Object Name: electronic calculator

Physical Description: plastic (case; keys; display; feet material)metal (circuitry material)Measurements: overall: 1 3/8 in x 3 in x 5 3/4 in; 3.4925 cm x 7.62 cm x 14.605 cm


Record Id: nmah_1305726

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