Gamma 10


In 1961, Bull's traditional punched card equipment business was in big jeopardy:

Compagnie des Machines Bull was obliged to rely on American RCA's licenses to survive. But a too much ignored internal project, the Gamma 10, initiated in that period, succeeded to be the first European computer to pass the 1,000th mark.

The Gamma 10 capitalized on 300cpm card reader and punch devices developed for Series 300 and also used the Bull drum I50 printer at 300 lpm. It was based on  a general purpose minicomputer with stored programs replacing the burden causing "connection panels" of tabulators. The computer controlled the peripherals, a change from the tabulator-Gamma 3 combination that the  Gamma 10 superseded.

central unit and Card reader/punch of Gamma 10 (FEB)


The Gamma 10 was built under the direction of Jacques Hannicq and Pierre Chenus. Jacqueline Vidal-Bailby designed the architecture.




The magnetic core main memory varied in sizes of 1024, 2048 or 4096 characters. Its cycle time was 7 µs.

gamma10.gif (42724 octets)

In 1967, a magnetic tape unit using 35mm film substrate (a Bull internal development for Small Systems) was also connnected to the Gamma 10.

In 1967-68, a data communication adapter (synchronous, 2400bps) was developed to try to use the Gamma 10 as remote batch computer. Considering the problems that plagued at that time the GE-600, the introduction of an another remote batch terminal did not encountered any significant success.


The first batch of systems were manufactured in Paris Gambetta (under the leadership of Marc Bourin). The production was then transferred at the then relatively new plant of Angers.


The Gamma 10 remained at Bull-General Electric's catalog after the 1964 merger, but GE sales resources did not have a card equipment customer base to sell it in the U.S. . So, it remained reserved to the European market (Bull-GE and GE-United Kingdom).

The extensions fell in face of the Olivetti-born GE-115 that was a more flexible computer not relying on relatively unit record equipment and manufactured at lower cost.

A Gamma 10 software emulator for the GE-400 was implemented circa 1967, to ease the conversion of Gamma 10 large punched card users to computers.


Revision : 06 décembre 2002.