The Société d'électronique et d'automatisme (SEA) was an early French computer manufacturer established in 1947 by electrical engineer François-Henri Raymond, which designed and put into operation a significant portion of the first computers in France during the 1950s. The SEA played a major role in driving the development of the French computer industry, training the first generation of engineers and installing about 170 computers between 1955 and its dissolution in 1966, when it merged with CII.
History and achievements In 1947, François-Henri Raymond was sent for a technical trip to the United States where he met with Howard H. Aiken at Harvard University, visited the MIT laboratories and came across John von Neumann's report on the EDVAC and the pioneering concepts of a then futuristic machine: the stored-program computer. Upon returning to Paris, he shared his ideas to produce such machines with his employer, a TV and radar manufacturer, but failed to convince him. François-Henri Raymond resigned and, without a formal business plan, established the Society of Electronics and Automation in December 1947, in a former automobile factory bombed during World War II. The startup's initial capital was contributed by a machine-tool maker, some of his friends, and Raymond's former employer. The SEA first client was the Air Force's missile bureau, whose operations demanded significant computational resources.
1949: analog computers SEA's inaugural computer, the OME 11, appeared in February 1949. This analog computer would set the stage for a series of subsequent models, including the OME 12, 15, 40, and 416 (OME was short for "Opérateur Mathématique Électronique"). While many were tailored for military applications, some models achieved a relative commercial success in the civilian sector. Notably, the OME L2 and P2 (1952), featuring vacuum tubes, and the transistor-based OME R (1959) stood out and were subsequently followed by a new generation of analog computers with the NADAC 20 (1961) and NADAC 100 (1962). SEA's analog computers enjoyed commercial success, with nearly 200 units sold and a strong international presence. They found diverse applications in fields such as physical, nuclear and hydrodynamic simulation - these machines were notably employed for flight simulations of the future Concorde aircraft. SEA also designed tailor-made analog computers for specific military applications.
1951: CUBA After securing a contract with DEFA (now known as DGA), SEA embarked on the development of its first stored-program computer in 1951, and France's first as well: the Calculatrice Universelle Binaire de l'Armement (CUBA). This contract provided SEA the opportunity to bring to life the digital computer plans it had been sketching since 1949, mainly based on John von Neumann's reports and the Cambridge EDSAC. The then ambitious technological choices made for CUBA lead to numerous delays. Notably, the decision to utilize cutting-edge magnetic core memories instead of the more established Williams tubes or mercury delay lines proved risky, as no manufacturer in the still World War 2 recovering French industry was yet capable of producing them. This challenge of sourcing components adhering to a novel set of requirements extended to many aspects, even reaching into wiring - SEA, as stated by its founder, was the first French company to employ ribbon cables and wire wrap.
Among other technological choices, SEA aimed to minimize the use of unreliable vacuum tubes, favoring instead germanium diodes for most of its logic and restricting tube usage to signal regeneration, a design first experimented with the SEAC (see diode logic). Additionally, an auxiliary drum memory was selected to complement the system, which SEA ultimately procured from the British company Ferranti due to the lack of a French manufacturer ready in time.CUBA was eventually delivered in 1954 and put into operation in 1956. With a three-years delay it became soon obsolete and was abandoned shortly thereafter. By that time, the French computer industry had already witnessed the emergence of other creations: SEA's own CAB 1011, a general computer which was used for cryptanalysis at SDECE (now DGSE), its CAB series 2000 and 3000 computers, and notably the Gamma 3 from Compagnie des machines Bull, introduced in 1952 and sold in quantities of around 1200 units. CAB stood for Calculatrice Automatique Binaire (Binary Automatic Calculator - the term "ordinateur", French for "computer", was coined only in 1955). The mid-1950s then marked a turning point for SEA, as the company went on to develop two transistorized computers, constituting its two large-scale productions in this field.
1956: CAB 500
Starting from 1956, SEA took an interest in the emerging potential of transistors, although their maturity at that time was yet to be proven. Among the alternatives, SEA explored magnetic logic, which was slower but notably reliable, making it suitable for a more compact-sized computer. In the same year, SEA invented the Symmag, a logic gate utilizing ferrite beads similar to those used in magnetic core memory. The Symmag would prove to be a central element in the architecture of the CAB 500, alongside a drum memory and sixteen 32-bit registers implemented on magnetic-core memory. The CAB 500 was a compact desktop computer designed to be operated by a single unskilled person, with minimal technical requirements for installation and operation. Furthermore, it was powered by one of the first interactive high-level languages, PAF, which facilitated its usage. The CAB 500 experienced immediate success, prompting the scaling up of production methods. Approximately a hundred units of the CAB 500 were manufactured and sold, with around a dozen units exported to countries including China and Japan.
1958: CAB 3900 Starting from 1958, SEA became a subsidiary of Schneider-Westinghouse, affording it increased industrial resources. This was also the juncture at which the decision was made to create a business computer, leveraging the experience gained from the CAB 2124 and 3030. Although primarily designed for scientific purposes, these machines were also used for business tasks, revealing a gap in the manufacturer's offerings.
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