Rockwell 9TR Handheld Electronic Calculator

This handheld electronic calculator has a green plastic case and eighteen rounded rectangular plastic keys. In addition to ten digit keys and a decimal point key, it has a clear entry/clear key, four arithmetic function keys, a total key, and a percentage key. A sticker above the keyboard reads in part: nheim. The on/off switch is on the left side. Behind the keyboard is an eight-digit LED display. Text behind the display reads: Rockwell. A jack along the back edge would hold a power adapter.
The back of the calculator has four feet and a compartment at the top for a nine volt battery. A sticker below this gives operating examples. Text near the bottom reads: Rockwell (/) International Microelectronics . . (/) Anaheim, CA . . . (/) Calculator Model 9TR (/) Assembled in Mexico (/) U.S. and Foreign Parts. Further text reads: Ser. (/) No. 167898.
According to Ball and Flamm, this model of a Rockwell calculator was especially manufactured for True Value Hardware stores. Compare the Rockwell 8R (1988.0988.12).
[Advertisement], Chicago Tribune, August 15, 1975, p. 8. Model 9TR advertised by a True Value hardware store as on sale for $14.88.
[Advertisement], Chicago Tribune, December 10, 1976, p. 19. Model 9TR advertised by a True Value hardware store as on sale for $7.99.
Guy Ball and Bruce Flamm, The Complete Collector’s Guide to Pocket Calculators, Tustin, CA: Wilson/Barnett, 1997, p. 126.
Currently not on view
Object Name
electronic calculator
date made
Rockwell International
Physical Description
plastic (case; keys; display cover material)
metal (circuitry material)
paper (sticker material)
overall: 1 in x 3 in x 6 in; 2.54 cm x 7.62 cm x 15.24 cm
place made
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

Visitor Comments

8/4/2016 10:45:01 PM
Emma Tompkins
I am sorry my calculator is a Rockwell Electronic Calculator with Percent Model 9TR Serial # 101252. The box is worn and someone did some addition in ink on the box and the paper tray it was in. There is a Owner's Manual with it. The calculator is in excellent condition.
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