Hewlett-Packard HP-35 Handheld Electronic Calculator

Hewlett-Packard HP-35 Handheld Electronic Calculator

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Usage conditions apply
The HP-35 was the first handheld electronic calculator to display all the functions represented on a slide rule. It has a black plastic case and a total of thirty-five square or rectangular plastic keys. These include ten digit keys, a decimal point key, and a pi key, all colored tan. In addition there are four arithmetic function keys left of the digit keys, a relatively long enter key, a change sign key, an enter exponent key, a clear x key, and a clear key, all in blue. Additional black keys are for powers, logs to base ten, natural logs, exponents, square roots, trigonometric functions (sine, cosine, tangent and the inverses of these), simple inverses, exchange, roll down, store, and recall. Above the keys is an on/off switch. There is no hole next to the switch to indicate that the display is on, as there was in the very first HP-35 calculators. Behind the switch is a red light emitting diode display that shows results. Numbers with absolute value between one hundredth and 10 billion are given in decimal form. Smaller or larger ones appear in scientific notation, with the appropriate power of ten occupying the three rightmost digit places (two for digits, one for a sign). The negative sign for the result, if needed, is at the far left. A mark on the front edge of the calculator reads: hp HEWLETT•PACKARD.
The back of the calculator has a plug for a three-prong power adapter (this example has no adapter), a compartment for a battery pack, four rubber feet, and a sticker entitled: HP-35 INSTRUCTIONS. Text below the sticker reads: HEWLETT-PACKARD (/) 3.75V SER. 1143A 25578 500mw (/) MADE IN U.S.A. PATENT PENDING. The first part of the serial number is printed, the last five digits are stamped with unit numbers 2 mm. high. A red sticker inside the battery pack reads: CAUTION (/) USE ONLY H. P. BATTERY PACK (/) MODEL NO 82001A (/) OTHER BATTERIES MAY DAMAGE CIRCUITS.
This calculator was part of the collection of John R. Priser. Who purchased it initially is not known.
W.A.C. Mier-Jedrzejowicz, A Guide to HP Handheld Calculators and Computers , Tustin, California: Wilson/Burnett Publishing, 1997, pp. 36–39, 132.
David G. Hicks, The Museum of HP Calculators, http://www.hpmuseum.org/, accessed July, 2014.
Thomas M. Whitney, France Rodé, and Chung C. Tung, “The ‘Powerful Pocketful’: an Electronic Calculator Challenges the Slide Rule,” Hewlett-Packard Journal, June 1972, pp. 2–9.
Currently not on view
Object Name
electronic calculator
date made
Hewlett-Packard Company
place made
United States
Physical Description
plastic (case; keys; display cover material)
metal (circuitry material)
paper (sticker material)
overall: 1 1/4 in x 3 1/4 in x 5 3/4 in; 3.175 cm x 8.255 cm x 14.605 cm
ID Number
catalog number
accession number
Credit Line
Gift of John B. Priser
See more items in
Medicine and Science: Computers
Handheld Electronic Calculators
Computers & Business Machines
Data Source
National Museum of American History
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