Unisonic 1299R-A Handheld Electronic Calculator

This handheld electronic scientific calculator has a metal and plastic case and an array of thirty-seven rectangular plastic keys. In addition to ten digit keys and a decimal point key, it has keys for trigonometric and inverse trigonometric functions, pi, logarithms, natural logarithms, exponents, powers of ten, general powers, inverses, squares, square roots, arithmetic functions, change sign, exchange, parentheses, and memory. Pushing an INV key at the top left allows some keys to perform a second function. Switches for radians/degrees/grad and for on/off are left of the INV key at the top of the keyboard. A mark above this reads: Unisonic 1299R. A green vacuum fluorescent display is behind this. It shows an eight-digit mantissa and a two-digit exponent, with signs for both.
A power jack is on the top edge.
The back of the calculator has a sticker describing calculation examples. It reads in part: 1299R-A. It also reads in part: SERIAL NO. (/) 032370 (/) MADE IN JAPAN. Below this is a compartment for four AA batteries.
The black plastic sleeve holds not only the calculator but a pamphlet with title Unisonic 1299R 8-Digit Scientific Slide Rule Calculator Instruction Manual. It describes the function of the keys in detail.
The case of this calculator is similar in style to 1986.0988.117 (Unisonic 790R-C), 1986.0988.118 (Unisonic 790RM-C), 1986.0988.116 (Unisonic 796-A), and 1986.0988.115 (Unisonic 799-A), which is used as the basis for a rough date of 1975. No advertisements found.
Currently not on view
Object Name
electronic calculator
date made
ca 1975
Physical Description
plastic (case; keys; carrying sleeve material)
metal (case; circuitry material)
glass (display material)
paper (sticker; instructions material)
overall: 1 3/8 in x 3 1/2 in x 6 in; 3.4925 cm x 8.89 cm x 15.24 cm
place made
ID Number
accession number
catalog number
See more items in
Medicine and Science: Computers
Handheld Electronic Calculators
Computers & Business Machines
Data Source
National Museum of American History, Kenneth E. Behring Center


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