Unisonic 1540L Handheld Electronic Calculator

This handheld electronic calculator has a metal and dark brown and tan plastic case and an array of twenty-five square plastic keys. These include ten digit keys, a decimal point key, a total key, four arithmetic function keys, and four memory keys. In addition the instrument has a change sign key, an exchange key, a square root key, a percentage key, and a clear entry/clear key. Above these is the on/off switch. Behind is an eight-digit red LED display. A mark at the back reads: Unisonic 1540L.
A jack for a power adapter is along the back edge. At the top of the back is a compartment for two AA batteries. A sticker inside it reads: 59545. A sticker near the base of the back reads in part: Remove batteries if unit unlikely (/) to be used for more than 7 days. (/) Made in Hong Kong.
[Advertisement], Ludington [Michigan] Daily News, August 29, 1977, p. 18. Unisonic 1540L on sale for $8.88, regularly $11.59.
[Advertisement], Grand Prairie [Texas] Daily News, August 11, 1977, p. 14. Unisonic 1540L on sale for $8.88, regularly $11.59.
Currently not on view
Object Name
electronic calculator
date made
ca 1977
Physical Description
metal (case; circuitry material)
paper (stickers material)
plastic (case; keys material)
overall: 7/8 in x 2 3/4 in x 5 3/4 in; 2.2225 cm x 6.985 cm x 14.605 cm
place made
Zhonghua: Hong Kong
ID Number
catalog number
accession number
Computers & Business Machines
Handheld Electronic Calculators
See more items in
Medicine and Science: Computers
Handheld Electronic Calculators
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of John B. Priser
Additional Media

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