In the light of the 50th anniversary of the existance of the Physics Laboratory TNO in the year 1977, computers and their use can be viewed as a late development with an explosive growth. The years 1964, 1970, 1971 and 1974 can be mentioned as the most important years with respect to the computer capacity of the Laboratory.
In the years preceding to 1964, the calculations and analyses were made using mechanical calculation machines which were operated by arithmeticians. This job took many man-hours. For instance, a matrix inversion of a simple 24x24 matrix took 5 man-hours behind a "Madas", an electrical powered calculating machine with a mechanical counter.
The Elliott/NCR 803B configuration comprised a memory of 8192 words with 39 bits, and had a cycletime of 576 microseconds. For storage of data, the Elliot used magnetic "film": three films of 262144 words (4096 blocks) with 29 bits. A word contained either two instructions or a number (12 decimals fixed point; 9 decimals floating point).
Additionally, the following input/output equipment became part of the configuration:
a 5- and 8-channels 500 characters per second (cps) papertape
reader, a 5- and 8-channels 100 cps papertape punch and later on a Calcomp
563 plotter. The software consisted of an assembler, Algol
60 compiler, a simple simulation package and a plotter package.
Soon the volume of work grew to such an extent, that the system had to be operated also outside the normal Laboratory working hours.
Paper tape/punch tape repair tool: at left cutting knive, in the middle the array of holes to punch the (new) tape.
The photo at the right shows a box of repair stickers for punch tape. (you can enlarge the enlarge photos by clicking)
An automatic telephone answering system was designed and developed by the Laboratory itself. By calling to this system, one could hear the sound from the computer's loudspeaker. From that sound, on ecould tell the progress that a certain computer program made or that the system halted. Was a parity error heard via the phone, the operator byked to the Laboratory to correct the error situation.
In the year 1965, one envisioned that the speed and the input/output equipment was too limited for the predicted use. For that reason, in 1966 additional computer capacity was acquired by using the computer of the "Afdeling Bewerking Waarnemingsuitkomsten TNO" (which later became IWIS-TNO) as well. In the next years, additional computer capacity was also acquired from Shape Technical Centre (STC).
It took until 1970 before the Laboratorium was able to to replace its computer system by a Control Data 3200 computer, although such a replacement was already requested in the mid of 1967.
Floorplan of the CDC 3200
The Control Data 3200 computer (Ref. CDC 3800 information) had a memory of 32K words of 24 bits, a cycle-time of 1.25 microsecond and an extended set of peripheral equipment, as hard disks, tape units, a card reader, a printer and a plotter. More on the Control Data 3000-series systems can be found on Wikipedia.
In 1971, the computer configuration was enlarged with a Control Data 1700 minicomputer and an interactive graphic display, called Digigraphic. The users used a light pen to input coordinates or commands.
The peripheral equipment of the CD 1700 consisted of a papertape station and equipment with possibilities to connect all kinds of peripheral equipment to the system. The project "Wargaming" required the interconnection of a colour television monitor and slide projectors to the CD 3200/1700 computer system. The interfaces were designed and developed by the Laboratory itself. The following software was used on the system: several compilers for high-level computer languages, as Algol, Fortran and Cobol and some computer packages.
The fast growing use of the computer system configuration already stimulated
thoughts about a replacement of the system in late 1972. In June, 1974 this
replacement took place. The CD3200 was exchanged
by a Control Data 6400 computer system. More details
about this system wil be explained later.
Such a big system could only be justified if "other people" would use this system for technical-scientific purposes for the Netherlands Armed Forces.
In the year 1975, the CD 1700 was replaced by a Control Data SYSTEM 17 minicomputer (in a later version called CDC System 18). The software for the interconnection of that minicomputer with the Control Data 6400 was developed by the system programmers, just like it was done for both predecessor systems. This interconnected complex of systems was called, the Control Data 6400/SYSTEM 17 computer system.
That system was also used by the other laboratories
of the "Rijksverdedigingsorganisatie (RVO)"
and by several groups in the Armed Forces.
Both the size of the computer system operations, and the diversity of users gave in 1975 cause to form a new group: the Computer group as offspring of the Mathematics/Operational Research group.