International Computers and Tabulators or ICT was a British computer manufacturer, formed in 1959 by a merger of the

British Tabulating Machine Company __NOTOC__ The British Tabulating Machine Company (BTM) was a firm which manufactured and sold Hollerith unit record equipment and other data-processing equipment. During World War II, BTM constructed some 200 "bombes", machines used at Bletchley ...

(BTM) and Powers-Samas. In 1963 it acquired the business computer divisions of

Ferranti Ferranti International PLC or simply Ferranti was a UK-based electrical engineering and equipment firm that operated for over a century, from 1885 until its bankruptcy in 1993. At its peak, Ferranti was a significant player in power grid system ...

. It exported computers to many countries and in 1968 became part of

International Computers Limited International Computers Limited (ICL) was a British computer hardware, computer software and computer services company that operated from 1968 until 2002. It was formed through a merger of International Computers and Tabulators (ICT), English Ele ...

(ICL).

Products

The ICT 1101 was known as the

EMIDEC 1100 The EMIDEC 1100 computer (became the ICT 1101 in 1962) was produced by the Computing Services Division of EMI Laboratories in the UK under the leadership of Godfrey Hounsfield in 1958, (first delivered in 1959) after one year's development. It us ...

computer before the acquisition of the

EMI EMI Group Limited (formerly EMI Group plc until 2007; originally an initialism for Electric and Musical Industries, also referred to as EMI Records or simply EMI) was a British transnational conglomerate founded in March 1931 in London. At t ...

Computing Services Division who designed and produced it. The ICT 1201 computer used

thermionic valve Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called ''thermions'' in early literature, ar ...

technology and its main memory was drum storage. Input was from 80-column

punched card A punched card (also punch card or punched-card) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were widel ...

s and output was to 80-column cards and a

printer Printer may refer to: Technology * Printer (publishing), a person * Printer (computing), a hardware device * Optical printer for motion picture films People * Nariman Printer (fl. c. 1940), Indian journalist and activist * James Printer (1640 ...

. Before the merger, under BTM, this had been known as the HEC4 ( Hollerith Electronic Computer, fourth version). The drum memory held 1K of 40-bit words. The computer was programmed using binary machine code instructions. When programming the 1201, the machine code instructions were not sequential but were spaced to allow for the drum's rotation. This ensured the next instruction was passing under the drum's read heads just as the current instruction had been executed. The

ICT 1301 The ICT 1301 and its smaller derivative ICT 1300 were early business computers from International Computers and Tabulators. Typical of mid-sized machines of the era, they used core memory, drum storage and punched cards, but they were unusual in ...

, and its smaller cousin the ICT 1300, used

germanium Germanium is a chemical element; it has Symbol (chemistry), symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid or a nonmetal in the carbon group that is chemically ...

transistor A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semicondu ...

s and

core memory Core or cores may refer to: Science and technology * Core (anatomy), everything except the appendages * Core (laboratory), a highly specialized shared research resource * Core (manufacturing), used in casting and molding * Core (optical fiber), ...

. Backing store was

magnetic drum Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory. Many early computers, called drum computers or drum machines, used dru ...

, and optionally one-inch-, half-inch- or quarter-inch-wide

magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic ...

. Input was from 80-column punched cards and optionally 160-column punched cards and punched

paper tape Five- and eight-hole wide punched paper tape Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop Punched tape or perforated paper tape is a form of data st ...

. Output was to 80-column punched cards, printer and optionally to punched paper tape. The first customer delivery was in 1962, a 1301 sold to the

University of London The University of London (UoL; abbreviated as Lond or more rarely Londin in Post-nominal letters, post-nominals) is a collegiate university, federal Public university, public research university located in London, England, United Kingdom. The ...

. One of their main attractions was that they performed British currency calculations ( pounds, shillings and pence) in hardware. They also had the advantage of programmers not having to learn

binary Binary may refer to: Science and technology Mathematics * Binary number, a representation of numbers using only two values (0 and 1) for each digit * Binary function, a function that takes two arguments * Binary operation, a mathematical op ...

octal Octal (base 8) is a numeral system with eight as the base. In the decimal system, each place is a power of ten. For example: : \mathbf_ = \mathbf \times 10^1 + \mathbf \times 10^0 In the octal system, each place is a power of eight. For ex ...

arithmetic as the

instruction set In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. A device or program that executes instructions described by that ISA, s ...

was pure decimal and the arithmetic unit had no binary mode, only decimal or pounds, shillings and pence. Its

clock A clock or chronometer is a device that measures and displays time. The clock is one of the oldest Invention, human inventions, meeting the need to measure intervals of time shorter than the natural units such as the day, the lunar month, a ...

ran at 1 MHz. The London University machine still exists (January 2006) and is being reinstated to working condition by a group of enthusiasts. The ICT 1302, used similar technology to the 1300/1301 but was a

multiprogramming In computing, multitasking is the concurrent execution of multiple tasks (also known as processes) over a certain period of time. New tasks can interrupt already started ones before they finish, instead of waiting for them to end. As a result ...

system capable of running three programs in addition to the

Executive Executive ( exe., exec., execu.) may refer to: Role or title * Executive, a senior management role in an organization ** Chief executive officer (CEO), one of the highest-ranking corporate officers (executives) or administrators ** Executive dir ...

. It also used the 'Standard Interface' for the connection of

peripheral A peripheral device, or simply peripheral, is an auxiliary hardware device that a computer uses to transfer information externally. A peripheral is a hardware component that is accessible to and controlled by a computer but is not a core compo ...

s allowing much more flexibility in peripheral configuration. The 'Standard Interface' was originally prototyped on the 1301 and went on to be used on the 1900 series. The ICT 1400 was a first generation computer using thermionic valves, but was overtaken by transistor technology in 1959 and no sales were made.. The ICT 1500 series was a design bought in from the

RCA RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent pool, patent trust owned by General Electric (GE), Westinghouse Electric Corporation, Westinghou ...

Corporation, who called it the RCA 301. RCA also sold the design to

Siemens Siemens AG ( ) is a German multinational technology conglomerate. It is focused on industrial automation, building automation, rail transport and health technology. Siemens is the largest engineering company in Europe, and holds the positi ...

in Germany and Compagnie des Machines Bull in France who called it the Gamma 30. It used a six-bit

byte The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...

and had core stores of 10,000, 20,000 or 40,000 bytes. The

ICT 1900 series 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-America ...

was devised after the acquisition of Ferranti's assets which brought in the new Ferranti-Packard 6000 machine from Ferranti's Canadian subsidiary, which was considerably more advanced than the existing 130x line. It was decided to adapt this machine to use the 'Standard Interface', and it was put on the market as the ICT 1904, the first in a range of upward-compatible computer systems. In 1968 ICT merged with English Electric Computers, itself formed from the prior mergers of English Electric Leo Marconi (EELM) and

Elliott Automation Elliott Brothers (London) Ltd was an early computer company of the 1950s and 1960s in the United Kingdom. It traced its descent from a firm of instrument makers founded by William Elliott in London around 1804. The research laboratories were o ...

. The resulting company became

(ICL). At the time of the merger English Electric Computers was in the process of making a line of large

IBM System/360 The IBM System/360 (S/360) is a family of mainframe computer systems announced by IBM on April 7, 1964, and delivered between 1965 and 1978. System/360 was the first family of computers designed to cover both commercial and scientific applicati ...

-compatible mainframes based on the

RCA Spectra 70 The RCA Spectra 70 is a line of mainframe computers and related electronic data processing (EDP) equipment that was manufactured by the Radio Corporation of America’s computer division beginning in April 1965. The Spectra 70 line included sev ...

, which was sold as the ICL System-4. Both 1900 and System-4 were eventually replaced by the

ICL 2900 Series The ICL 2900 Series was a range of mainframe computer systems announced by the British manufacturer International Computers Limited on 9 October 1974. The company had started development under the name "New Range" immediately on its formation ...

which was introduced in 1974.

External links

Oral history interview with Arthur L. C. Humphreys (1981)

Charles Babbage Institute The IT History Society (ITHS) is an organization that supports the history and scholarship of information technology by encouraging, fostering, and facilitating archival and historical research. Formerly known as the Charles Babbage Foundation, ...

, University of Minnesota. Humphreys, a former managing director of ICL, reviews the history of the British computer industry, including the merger in 1959 of

and the Powers Samas company into International Computers and Tabulators, Ltd. (ICT), and the merger in 1968 of English Electric Computers Limited and ICT into ICL.
Boards from the ICT 1301
– archived in November 2006
ICT 1301 Resurrection Project
–

The National Museum of Computing The National Museum of Computing is a UK-based museum that is dedicated to collecting and restoring historic computer systems, and is home to the world's largest collection of working historic computers. The museum is located on Bletchley Par ...

Two articles on the HEC4 at Morgan Crucible Co
– archived in April 2014

References

{{Authority control Defunct computer companies of the United Kingdom * Defunct computer hardware companies Defunct computer systems companies Defunct manufacturing companies of the United Kingdom Former defence companies of the United Kingdom Computer companies established in 1959 Electronics companies established in 1959 Computer companies disestablished in 1968 Electronics companies disestablished in 1968 1959 establishments in England 1968 disestablishments in England British companies established in 1959 British companies disestablished in 1968