Friden, Inc.

Friden Calculating Machine Company (Friden, Inc.) was an American manufacturer of typewriters and electronic calculators. It was founded by Carl Friden in San Leandro, California in 1934. Friden electromechanical calculators were robust and popular.

In 1957, Friden purchased the Commercial Controls Corporation of Rochester, New York. This gave them the Flexowriter teleprinter, an electric typewriter capable of being used as part of Unit record equipment, predecessor to modern computers. The Flexowriter could be attached to Friden calculators and driven by paper tape to produce bills and other form letters which had names of customers and amounts of bills filled in automatically. Friden eventually expanded into production of a few models of early transistorized computers.

Friden introduced the first fully transistorized desktop electronic calculator, the model EC-130 in June 1963. This machine had a 13-digit capacity and a 5-inch CRT display. It used a form of acoustic delay line for memory, to save money on expensive transistors. The EC-130 sold for $2200, about three times the price of comparable electromechanical calculators of the time. It was the first calculator to use reverse Polish notation (RPN), which eliminated the need for parentheses to specify the order of operations in complex calculations. The successor model EC-132 added a square root function.

In 1965 the company was purchased by the Singer Corporation.

External links

* [http://www.oldcalculatormuseum.com/fridenstw.html Friden STW-10] Electromechanical calculator sold from 1949–1966
* [http://blinkenlights.com/classiccmp/friden/ Friden Flexowriter] combination typewriter and paper tape punch, designed by IBM during the 1940s and bought out by Friden in the late 1950s (Retrieved April 10, 2007)
* [http://www.oldcalculatormuseum.com/friden130.html Friden EC-130] Electronic calculator (1963)
* [http://www.oldcalculatormuseum.com/friden132.html Friden EC-132] Electronic calculator (1965)
* [http://www.oldcalculatormuseum.com/fri1112.html Friden/Singer 1112] with 507 transistors and twelve digit Nixie tube display, designed and built by Hitachi