Radio Shack EC-490 Handheld Electronic Calculator
date: label: date made
content: 1976
name: label: maker
content: Tandy Corporation
notes: label: Description
content: The 1976 Radio Shack catalog advertised this handheld electronic calculator as “our finest scientific slide-rule calculator.” At a list price of $99.95, it was described as “a superb buy.” The calculator has a tan, black, and brown plastic case with an array of twenty-five sloping plastic keys. These include ten digit keys, a decimal point key, a pi key, four arithmetic function keys, a total key, an exchange key, and two parentheses keys. The top row of keys includes a clear entry/clear key, an EE (enter exponent) key, a change sign key, a function key, and an ARC key.
label: Description
content: Many of these keys had a different effect if the F or ARC key was pushed. Functions found in this way include inverses, exponents, powers, logarithms, square roots, trigonometric functions, inverse trigonometric functions, conversion from radians to degrees, conversion from degrees to radians, and factorials. The calculator also has memory keys. Behind the keys are a degree/radian switch and an on/off switch. Behind the switches is a twelve-character vacuum fluorescent display that shows results in scientific notation, including eight digits of the result, two digits of the exponent in base ten, and the sign of both the number and the exponent. The back edge of the calculator has a jack for a power supply.
label: Description
content: A sticker on the back describes operating procedures. Text near the bottom reads: RADIO SHACK A TANDY CORPORATION COMPANY (/) FORT WORTH, TEXAS 76107. Further text reads: Calculator Model EC-490 (/) Catalog Number 65-635 (/) Assembled in Mexico. A further mark reads: Ser. No. (/) 108809.
label: Description
content: The calculator has an imitation leather carrying case. Text on the front reads: Radio Shack.
label: Description
content: Compare this device to calculator 1986.0988.163, a Rockwell 63R.
label: Description
content: References:
label: Description
content: Radio Shack, A Tandy Company, <i>1976 Electronics Catalog </i>, p. 117, accessed September 22, 2014, at radioshackcatalogs.com.
label: Description
content: Guy Ball and Bruce Flamm, <I>The Complete Collector’s Guide to Pocket Calculators</I>, Tustin, CA: Wilson/Barnett, 1997, p. 121.
label: Location
content: Currently not on view
place: label: place made
content: Mexico
setName: label: See more items in
content: Medicine and Science: Computers
label: See more items in
content: Computers & Business Machines
label: See more items in
content: Handheld Electronic Calculators
creditLine: label: Credit Line
content: Gift of John B. Priser
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1986.0988.036
label: catalog number
content: 1986.0988.036
label: accession number
content: 1986.0988
objectType: label: Object Name
content: electronic calculator
label: Other Terms
content: electronic calculator; Handheld
physicalDescription: label: Physical Description
content: plastic (case; carrying case; keys material)
label: Physical Description
content: metal (trim; circuitry material)
label: Physical Description
content: paper (sticker material)
label: Measurements
content: overall: 1 in x 3 3/8 in x 6 in; 2.54 cm x 8.5725 cm x 15.24 cm