Relay type computer AL-1

Relay type computer AL-1

Relay type computer AL-1



Manufactured in 1962
Manufactured by CASIO COMPUTER CO., LTD.
Owner UEC Museum of Communications, The University of Electro-Communications
Location of historical materials The University of Electro-Communications
1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 Japan
Visitor information Open to the public (Reservation required)
Contact UEC Museum of Communications, The University of Electro-Communications
Tel.+81-42-443-5296


CASIO COMPUTER completed a trial manufacture of a relay type computer at the end of 1956, commercialized "14-A" in 1957, and released "14-B" which can calculate the square root in 1959. They developed "301" which can also exchange programs for science and technology calculations in 1960. "AL-1" corresponds to its successor, is a decimal computer, the basic operations are four arithmetic operations and square root. The numerical value is ten digits and the internal representation of the number is bi-quinary coded decimal. A variable can store one pair of ten digits, and constants can store two sets of ten digits. Nixie tubes are used for the display. In the unit of six resin gears with 60 teeth, the user himself sets up a program of 6 bits 58 steps and can perform calculation automatically by the preset calculation procedure. This unit can be removed and multiple calculation procedures can be swapped as needed. About 500 relays are used, the size of the main body is 110×113×42 (cm). The price at the time was 995,000 yen.

"AL-1" is a computer that adopts the ten-key system with the √ symbol added, which is a product that led to the birth of a electronic calculator thereafter. This product is registered in the important science and technology history documents (future technical heritage) sponsored by the National Science Museum in 2014 as an indication of the process of its development. "AL-1" owned by the University of Electro-Communications is preserved in an operable state.