The 1301 from International Computers and Tabulators (ICT) included a number of distinguishing technologies and features that made it unique.

The use of decimal instead of binary logic made it easier to program and it featured the ability to handle pre-decimalisation currency - pounds, shillings and pence. The ICT 1301 featured a high-speed printer that was capable of 600 lines per minute so users could quickly print their data outputs and, also, no longer had to rely data output to hole-punched paper tape or cards. Storage on magnetic tape was added later for even greater capacity - up to eight metal and glass cabinets containing magnetic tape reels for further storage.

But two features made the ICT 1301 really stand out: the 1301 was ICT’s first computer to adopt germanium transistors and magnetic core memory. Both were new at the time and were stepping stones to smaller, reliable, more powerful computers produced at lower cost.

Developed in the US by Bell Laboratories in 1947, germanium transistors replaced vacuum tubes used in earlier computers. Germanium transistors were more reliable than vacuum tubes, they consumed a smaller amount of power, weren’t as fragile, and physically smaller in size. The ICT 1301 consisted of 7,352 germanium transistors on 4,000 printed circuit boards.

Magnetic core memory, used successfully for the first time in 1953, consisted of a mesh of tiny metal rings hand woven together and magnetised to represent zeroes and ones. ICT branded its version of magnetic core memory Immediate Access Storage, reflecting its ability to retrieve data faster than technologies like rotating drums that made it suited to larger and more complex data-query work. IAS also had greater capacity - 100,000 cores and the 1301 a main memory of up to 12,000 bytes.

The ICT 1301 has a corporate connection that extends to code breaking and Alan Turing at Bletchley Park during the Second World War.

The 1301 belonged to International Computers and Tabulators - ICT - but ICT came into existence in 1959, midway through the computer’s development. ICT resulted from the merger of Powers-Samas, famous for punched-card machines, and the British Tabulating Machine Company (BTM) which dominated the UK and Commonwealth market for these machines.

Tabulators were electromechanical devices used widely in business and government to process and collate large amounts of data stored on punched cards. BTM’s experience meant the British Government awarded it the job of building and assembling another type of electromechanical device - the Bombe, which helped codebreakers decrypt radio messages sent by the German military encoded using Enigma. Alan Turing and Gordon Welchman are credited with the Bombe’s design. Their machine automated the process of finding patterns in encrypted messages to identify each message’s key and therefore help codebreakers crack the message.

Construction and delivery of Turing and Welchman’s creation was handled by BTM’s factories in Letchworth, Hertfordshire - the company dedicated 70 percent of its manufacturing capacity to the job. The first machines took six months to build but production ramped up to one a week once Bombes were produced in batches. Finished machines were dispatched by army lorry - with just a single soldier as escort - either to Bletchley Park 53km (33 miles) away or one of its outstations.

The ICT 1301 was one of the first successful British-made business computers. Dr Raymond Bird was its designer - but the 1301 wasn’t his first success.

Bird joined the British Tabulating Machine Company (BTM) - which became ICT - from GEC where he'd worked on improving vacuum tubes that were used by the first generation of digital computers. BTM recognised computers were coming but was concerned by their tendency to be expensive and built for just a single purpose. Bird undertook a fact-finding mission during which he met Dr Andrew Booth of Birkbeck College in London. It was a critical moment: Booth shared his design for a computer that could be affordably produced for a big market. Bird led a team which built the prototype that became the Hollerith Electronic Computer (HEC) - now on display at TNMOC - which copied Booth’s circuitry but added extra interfaces. Bird would refine the prototype and deliver subsequent models with the HEC4, marketed as the BTM1200, becoming the biggest selling British computer of the 1950s by volume: 70 were sold.

Bird was set the task of designing the 1200’s successor and was transferred to Computer Developments Ltd, a subsidiary BTM created with GEC to complete the mission. Bird wanted to marry technical innovation and commercial capabilities but - by his own admission - the 1301 was more complicated than anything yet undertaken. It had been possible for a relatively small number of individuals to design and build the first commercial computers but BTM’s strategy for the 1301 changed this. New technologies and capabilities created complex challenges and more sophisticated subroutines - a bigger team was needed.

Software was one issue. Until now, BTM had provided customers with certain subroutines and trained them to programme their machine. The 1301 turned this on its head. The magnetic core, for example, demanded new control routines that had to be written by BTM using a large team of 20 programmers working round the clock. The 1301 introduced storage on magnetic tape that wouldn’t synchronise properly so Bird had to design a new system of error detection and correction to overcome this. ICT also had to source a reliable magnetic tape drive and a printer, both of which came from the US and entailed trips to meet the suppliers.

Ultimately, however, these challenges would be overcome and Booth’s design for the 1301 was realised, with enviable sales during its lifetime of more than 200.

As new and faster computers began to replace the ICT 1301s, a second life beckoned for the very first machine to go into use - the University of London’s machine.

Unable to afford computers of the time, many firms and individuals would pay for computing services. In 1973 Galdor Computing, formed by a band of friends who bought the University of London’s 1301, began selling these services operating in the back garden of their south London home.

Friends Stuart Fyfe, Trevor Jarrett, Andy Keene and Derek Odell, had originally decided to buy a second-hand computer while studying at Kingston Polytechnic. They had planned to use the computer for remote control of the Kenley Astronomical Telescope for the Croydon Astronomical Society, so scraped together £200 to buy the University’s 1301. They beat scrap-metal dealers who’d offered thousands of pounds - the University was happy to see its computer continue in the service of education.

The friends dismantled the 5.5-tonne, steel-framed machine over a period of two weeks and moved it by lorry but it was an inheritance from Andy’s great aunt Florence that finally allowed the friends to get their 1301 up and running - earning the 1301 her new name. Flossie was installed in a prefabricated house over a six-month period and Galdor soon built a base of 35 customers. This gave them the skills to take on a massive job: a six-month operation running for 24-hours a day towards the project’s end processing records and reports for Liverpool Victoria Insurance as the insurance giant switched to newer computers. Spare parts for Flossie were sourced from other 1301s as they were retired for scrap.

Galdor upgraded to an ICL 1900 in 1977 and sold Flossie - for £200.

Catch Stuart as he discuss his experiences with the 1301 in our video: Second life for an ICT 1301 called Flossie

BTM - which became ICT - dominated the British and Commonwealth business market for punched-card data processing but the world was changing: digital computers started to replace electro-mechanical tabulators that had been widely used to process punched cards.

BTM wanted to convert its tabulator customers to computers but faced stiff competition: EMI, English Electric, Honeywell and LEO at home while - from the US - came IBM: IBM released the world’s first commercial, germanium-transistor computer and followed up with the 1401 while the 1301 development. Nearly 100 IBM 1401s were installed in the UK between 1961 and 1962 - accounting for third of computer sales with the majority replacing tabulators from what had become ICT.

BTM had wanted an affordable, small commercial computer and decided to partner with an electronics manufacturer to deliver. It partnered with GEC in Coventry - a specialist in telecoms equipment - for its manufacturing skills, expertise in making reliable systems, an ability to quickly adapt to changes in computer memory and processor technology, and because it had not declared intention of marketing computers. The companies formed Computer Developments Limited to work on computer designs that included the 1301 but IBM’s 1401 accelerated 1301 development.

The first 1301 - serial number six, which became Flossie - was installed at the University of London in 1962. It was used to process student exams results and process administrative work.

The combination of a speed of magnetic core memory, 1MHz clock speed and parallel data transfer made the 1301 suited to complex and intensive data-processing tasks for customers.

1301s were therefore used in aircraft design work, insurance policy calculations and billing large insurance firms, calculation of local authority rates, timetabling and rolling stock calculations for the national railways, payroll for large companies and government departments. Customers included the Department for Education and Science, Metropolitan Police, British Rail Freight, John Lewis Partnership and Liverpool Victoria Insurance. The 1301 started at £100,000 for a “basic” model.

The ICT 1301 was good looking and practical - for that, credit goes to Noel London of the award-winning industrial design consultant London and Upjohn.

The 1301 was among a generation of computers that exchanged valves and cumbersome memory units for transistors and cores. This not only helped them become more powerful it made them smaller - albeit the ICT 1301 still occupied 65 square meters (700 square feet) of floor space - allowing them to be used in more workspaces.

It therefore became possible - and increasingly desirable - to hide the inner workings. The ICT 1301 weighed over five tonnes and was built around a steel and iron frame that ranged in thickness from a quarter to two inches. Probe inside and you risked electrocution - the back of the console contained bare electrical terminals conducting 440v AC.

Moreover, as computers left the laboratories where they’d been built and programmed, it became vital they could be understood and operated by everyday users.

Some systems were packed inside metal cases or built into desk-like structures. London and Upjohn adopted a modern, industrial chic. A control console was angled at just the right position for both standing and sitting, disciplined lanes of lights, buttons and dials were all angled and positioned within easy reach, as were the punched-card trays. All this was housed in a casing of modern polished metal and grey.

The design is credited to London with the console winning recognition by the British Design Council which was working to promote excellence in British manufacturing. The ICT 1301 would receive the Council’s black and white triangle tag that recipients could use in advertising and marketing to help promote the quality of their design.

The 1301 appears to have been the start of a rewarding partnership between ICT - which became ICL in 1968 - and London and Upjohn. The consultancy worked on the 1900 which succeeded the 1301, with the 1904A model earning a Council of Industrial Design award in 1970 and the ICL 2904 a Design Council Award in 1977.

The work of London and Upjohn spanned the decades. From telephones for the General Post Office to fork-lift trucks, their minimalist and functionally efficient work would receive further recognition from the Design Council in 1980.