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Hewlett-Packard HP 11C Handheld Electronic Calculator

Hewlett-Packard HP 11C Handheld Electronic Calculator

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Usage conditions apply
This handheld programmable scientific calculator has an array of thirty-nine plastic keys. Most of these can take on three different meanings. One is indicated in white atop the key, one in orange on the keyboard behind the key, and one in blue on the sloping front of the key. In addition to representing digits, arithmetic functions, trigonometric and inverse trigonometric functions, square roots, powers, logarithms, natural logarithms and the number pi, keys can be used to compute various statistical functions. Additional keys are used in setting up programming routines.
The LCD display behind the keyboard exhibited results in common form or in scientific notation.
A mark on the front of the calculator reads: hp (/) 11C. A mark at the bottom of the front reads: HEWLETT-PACKARD. A paper tag taped to the back of the calculator gives an elaborate trigonometric formula. A compartment on the top left holds three silver-colored batteries.
According to Mier-Jedrezejowicz, the HP-11C was introduced in 1981 and discontinued in 1989. This example has a serial number on the back of 2534A49130. This indicates that the calculator was made in the thirty-fourth week of 1985 (25 years after 1960) in the United States (A).
The calculator has a black plastic sleeve. A mark on it reads: hp.
This example of the calculator was owned by Tom Simkin, Curator of Volcanology in the Department of Mineral Sciences at the Smithsonian’s National Museum of Natural History.
Accession file.
W.A.C. Mier-Jedrzejowicz, A Guide to HP Handheld Calculators and Computers , Tustin, California: Wilson/Burnett Publishing, 1997, pp. 70–71, 133.
David G. Hicks, The Museum of HP Calculators, http://www.hpmuseum.org/, accessed July, 2014.
Accession file.
Currently not on view
Object Name
electronic calculator
date made
Hewlett-Packard Company
place made
United States
Physical Description
plastic (case; keys; envelope material)
metal (trim; keyboard material)
paper (tag material)
overall: 1.9 cm x 13.5 cm x 9 cm; 3/4 in x 5 5/16 in x 3 17/32 in
ID Number
catalog number
accession number
Credit Line
Gift of Sharon Simkin
See more items in
Medicine and Science: Computers
Computers & Business Machines
Handheld Electronic Calculators
Data Source
National Museum of American History
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The best calculator I have ever owned. Bought it in 1985 and just changed the batteries (2021) Cheers
I love this calculator! still use it regularly since purchasing in 1985. on second set of batteries. the nicest feel to the buttons, excellent use. Wish i could purchase new, and love revers polish operation. HP should reintroduce.

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