ICT 1900 was a family of mainframe computers released by International Computers and Tabulators (ICT) and later International Computers Limited (ICL) during the 1960s and 1970s. The 1900 series was notable for being one of the few non-American competitors to the IBM System/360 , enjoying significant success in the European and British ...

ICT (International Computers and Tabulators) on 28 September 1964 announced the 1900 Range of systems, giving great emphasis on program compatibility and portability between all models in the 1900 range (present and future) and modularity via the ICT Standard Interface (“Each 1900 system will grow with the customer’s needs by replacing individua...

2-3 Performance of ICT / ICL 1900 Series (All Models) and derivatives 2903/ME29 (by Virgilio Pasquali) In a compatible range, addressing a wide and continuous span of the market, it became increasingly important to position each model in the range relative to the other models.

ICT announced a range of seven 1900 system models (1902, 1903, 1904, 1905, 1906, 1907, and 1909), Programming Aids (Software) and peripherals.

ICL - VME 2900 - Implementing a Transaction Processing System (TPMS 320) ICL 1900 Basic Peripherals. ICL 1900 Series 1900 Driver. ICL 1900 Series Analysis of Massive Survey Files. ICL 1900 Series Central Processors. ICL 1900 Series COBOL. ICL 1900 Series COBOL Compilers.

ICL 1900: The new computer room at the Cooperative Wholesale Society (CWS) Menswear Factory in Holbeck, Leeds around 1965. Here the ICL / ICT 1903 system used four magnetic tape units as its sole data storage medium - with punched cards as the input source.

The ICT 1900 Series, announced in 1964 and with first delivery the following year, originated in Canada as the Ferranti-Packard 6000. ICT developed this initial machine into a compatible range of eight models with performance spanning a range of roughly 1:20.

The ICL 1900 Series was announced in reaction to IBM’s System/360, but delivered, working well, before IBM’s offering. Both ranges consisted of upward-compatible computer systems designed to support commercial data processing and scientific number crunching, although the 1900 Series was not aimed at supercomputer performance.

ICT selected the FP6000 as the basis of their range and this speeded up the ICT/Ferranti merger. The 1900 Series was announced in September 1964, only six months after IBM launched System/360 and some 1900 models were delivered earlier than their IBM equivalents. The FP6000 was based on logic cards developed in Ferranti Wythenshawe for Orion 2.

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