Friden 132 electronic calculator

UvA Computer Museum catalogue nr 93.21

friden 132
The Friden Model 132 electronic calculator (1965) has the four basic arithmetic functions: add, subtract, multiply and divide. Square-rooting was an optional feature (not present on our Model 130 machine, nr 06.14); compared to the electromechanical calculators of the time this was a major improvement, besides speed, quiet operation and robustness.
The Friden 132 calculator uses 'reversed polish notation': 2+(3/8) is keyed in as 2 enter 3 enter 8 / +.
This principle, which obviates the use of parentheses, was later followed in the well-known pocket calculators of Hewlett-Packard.
The results of the computation are shown on a small CRT screen. The machine is built from separate transistors, memory is implemented using a magnetostrictive delay line.

The CRT (its socket protruding from the machine's enclosure) has a sticker warning for the 3 kV high tension.
The calculator logic is on four card-pairs with discrete transistors and passive components.

The machine is a fine example of careful industrial design. At its introduction in 1965, the calculator cost US$ 1950 - the price of a car.
Our Friden 132 has been in use at the UvA Medical Physics Laboratory.
The website of the Old Calculator Museum provides a detailed description, including an explanation of the machine's ingenious square-rooting algorithm.
Rev. February 7, 2017.