Plessey Co

January 1952.

January 1952.

The Plessey Company - an electronics, defence and telecommunications company.

General History

  • 1917. 12th December. Plessey was founded in Marylebone, London as a mechanical engineer, manufacturing jigs and tools, supplying other companies. The company was formed specifically to take advantage of the talents of a German-born engineer, William Oscar Heyne, who had been interned at the start of World War 1. The original shareholders were Thomas Hurst Hodgson, Raymond Parker and his brother Plessey Parker, and C. H. Whitaker, a school friend of Heyne's. There are various ideas about the origins of the company’s name - it is said to have been taken from the birthplace of Heyne’s wife, as well as from Plessey Parker but Hodgson was also brought up close to Plessey in Northumberland. Heyne was the sole employee initially, and went on to become one of the key figures in the development of the company during the 1920s and 30s. However, for the first few months, Heyne spent most of his time working as engineering consultant for other Hodgson companies including a galvanising company called British Electro-Chemists
  • 1919 The company moved to larger premises in Holloway. An American, Byron G. Clark, who was a shareholder in British Electro-Chemists, invested in Plessey, receiving 640 shares.
  • 1922, Byron Clark’s son, Allen George Clark, started working for the company.
  • 1922 Byron Clark seems to have been connected to Norman De Maid Watsham and A. H. S. MacCallum who founded British Radiophone Ltd. Watshams won an order from Marconi for 2 types of crystal set and a valve receiver; it is unclear what role British Radiophone Ltd played in this order but the order for crystal sets was sub-contracted to Plessey Co. This was the start of Plessey’s diversification into radio and electronic manufacturing. Plessey’s business model became a combination of mass-production of standard components for the makers of radio sets and sub-contract manufacture but not selling direct to the private customer. The manufacture of electrical components became a key area of growth for Plessey, eventually manufacturing a vast array of different components, many under licence from overseas companies.
  • 1923 Plessey moved to larger premises in Ilford. At the time there were more than 200 employees.
  • The shareholders of British Radiophone Ltd were persuaded to take shares in Plessey in exchange for Plessey being able to supply Marconi directly. But Marconi then demanded a stake in the growing company, which could not be refused as it accounted for 80% of Plessey's turnover. Marconi appointed 3 representatives to the board of Plessey
  • 1925 15th February. A new company was incorporated with a similar name and larger share capital to take over the original Plessey company formed on the 12th December 1917.
  • 1925 25th February. 'In the Matter of the PLESSEY COMPANY Limited. At an Extraordinary General Meeting of the above named Company, duly convened, and held at 7, Ely-place, Holborn-circus, E.G. 1, on the 7th day of February, 1925, the following Resolution was duly passed; and at a subsequent Extraordinary General Meeting of the Members of the said Company, also duly convened, and held at the same place on the 24th day of February, 1925, the same Resolution was duly confirmed as a Special Resolution, namely: — "That the Company be wound up voluntarily." And at such last mentioned Meeting, Harold Handley, of 7, Ely Pplace, E.C.1, was appointed Liquidator for the purpose of the winding-up. Dated this 25th day of February, 1925. (221) W. O. HEYNE, Chairman.'
  • Early 1925 Plessey Co was supplying 1300 radio sets/week to Marconiphone
  • 1925 13th March British Radiophone Ltd was placed into voluntary liquidation
  • 1925 Byron Clark became chairman of the new company with Allen Clark and W.O. Heyne as joint managing directors. Allen Clark’s sons John and Michael later both rose to prominent positions in the company.
  • By September 1925, Plessey was supplying 2,500 sets/week to Marconiphone
  • 1926 Marconiphone bought their own manufacturing company so orders to Plessey Co ceased
  • 1927 Henry Morgan appointed chairman - Morgan had been one of Marconi's appointments on the Plessey board.
  • 1928 Important contracts included production of telephones for the General Post Office (GPO) and items for the Air Force and the car industry. Production of equipment for professional customers became a growing part of the company’s business.
  • In 1929 John Logie Baird’s first production televisions were manufactured by Plessey. The company also produced the first British-made portable battery radio, the “National” which was supplied to Symphony and Columbia. Allen Clark introduced “mass production” which allowed the company to undercut its competitors in component supply.
  • 1930 Plessey presented a petition to wind-up the Symphony Gramophone and Radio Co
  • 1934 Review and image of Plessey Model AC.44 Airborne Transmitter Receiver
  • 1935 The workforce reached 3,000.
  • 1936 Clark and Heyne negotiated a number of key manufacturing licences from American companies, such as Breeze Corporation, for aircraft multi-pin electrical connectors; Federal Laboratories for Coffman starters (an explosive cartridge device used to start aircraft engines); and Pump Engineering Services Corporation for the manufacture of Pesco fuel pumps. Plessey went on to produce large numbers of Pesco fuel pumps for Rolls-Royce Merlin engines, and in 1940 the fuel pump for Britain's first jet engine. Also see Aircraft Industry Suppliers.
  • 1937. 17th March. In order to raise extra capital to fund expansion, essentially to take advantage of opportunities presented by rearmament, Plessey became a public company with a listing of its shares on the London Stock Exchange[4]. The new Machine Products subsidiary in Cardiff received an order for bomb casings from the Air Ministry and another, London Metal Products, received an order for trench mortar bombs.
  • 1939 The workforce reached 5000.
  • WW II - During the war, Plessey produced many different types of components and equipment for the war effort, including shell cases, aircraft parts, and radio equipment such as the R1155 (receiver) and T1154 (transmitter). Following the bombing of its Ilford site, Plessey converted a tunnel, built as an extension of the London Underground Central Line, into a munitions factory. The company also built a new factory at Swindon, and opened several other shadow factories around the U.K. The small research and development activity was moved to Caswell House, near Towcester. The wartime workforce grew to over 11,000.
  • 1946 With the coming of peace, the company shrank back to its core activities of radio, television and components; the workforce was reduced to 6000. In this year Byron Clark died. At the end of the year, Heyne retired, recognising that he "couldn't go on without Clark", the "American gentleman" as he called him
  • 1947 EMI placed an order for at least 100,000 radio and television sets.
  • 1949 Plessey entered the hydraulics field. John Allen Clark joined the company.
  • 1950 Michael William Clark joined Plessey and was appointed head of the Electronic Division. The number of research staff at Caswell reached 50, investigating new areas of business including ceramics, piezo-electric materials, ferrites, radar-absorbing materials, and tantalum capacitors.
  • 1951 The new Communications Division was formed, with Michael Clark at its head, and a remit to catch up with its competitors in VHF and UHF equipment. Two senior managers, John Cunningham and Raymond Brown, left Plessey to form Racal. A licence was obtained from the US company Philco for the manufacture of semiconductors; the two companies set up a joint venture.
  • 1952 A plant for making pure Silicon was established but the potential of the new field of “solid state technology” (the name given to it by Plessey) was not fully recognised.
  • 1957 Manufacture of transistors began at Swindon. Plessey also manufactured the first VHF/UHF airborne radio in the UK.
  • 1958 Royal Radar Establishment placed a contract with Plessey for integrated circuits. A new factory was opened at Cheney Manor (Swindon) for large-scale manufacture of Germanium transistors. Plessey purchased Garrard Engineering and Manufacturing Co, a company to which Plessey had lent factory space at Swindon after a fire. This was the start of a new approach to growth of the company - one of acquisition.
  • 1959 The workforce was 20,000.
  • 1960 At this time Plessey, Phoenix Telephone and Electric Holdings and the Telephone Manufacturing Co were the 3 smaller suppliers in the telephone supply industry. Other suppliers included AEI, Automatic Telephone and Electric Co, Ericsson Telephones Ltd, GEC, Marconi's Wireless Telegraph Co and STC.
  • 1960 A consortium of AEI, Automatic Telephone and Electric Co, Ericsson TelephonesLtd, GEC, Marconi's Wireless Telegraph Co, Plessey Co and STC formed a holding company Combined Telephone Holdings only days after its members had failed in their bid to acquire Telephone Manufacturing Co. Combined Telephone Holdings purchased for cash more than half of the shares in Phoenix Telephone and Electric Works and offered to purchase the rest
  • 1961 Plessey ceased radio and TV manufacture. Plessey took over two other telephone manufacturers, Ericsson Telephones Ltd and the Automatic Telephone and Electric Co doubling Plessey’s size to become Britain's largest manufacturer of telecommunications equipment[(including the majority of the country's crossbar switches / exchanges). Philco pulled out of the Semiconductors JV, selling its shares to Plessey. The change in nature of the company from manufacturer of components to provider of complete systems took place faster than the evolution of Plessey’s corporate planning leading to problems in later years.
  • 1961 Plessey had 23 subsidiary companies , employing 17,500 persons. These included designers and manufacturers of radio and television apparatus and components, electronic equipment, telecommunication equipment, electrical equipment, electrical instruments and commercial hydraulic power systems, makers of general light engineering products and atomic energy power control equipment.
  • 1962 Sir Allen Clark died. After boardroom disagreements, John Clark became MD; several directors resigned. Plessey were partners in the development of the Atlas Computer.
  • 1963 Plessey took over Ducon (Australian telecommunications equipment and components manufacturer) followed by many other purchases in the following years. Development of an electronic telephone exchange (TXE2) started.
  • 1965 US management consultancy McKinsey was brought in to review the company; the businesses were divided into Groups: Automation, Components, Dynamics, Electronics, Telecommunications, Overseas. Plessey Telecommunications would incorporate Ericsson Telephones and Automatic Telephone and Electric Co
  • 1966 MOS integrated circuits were produced at Swindon, making Plessey the first European manufacturer of such microcircuits.
  • 1967 The 68,000 employees included 6,500 in research and development with R&D labs at Caswell, Roke Manor, Taplow, Havant and Poole.
  • 1968 Plessey made an offer to buy English Electric Co: 'the largest takeover by value in British history' but lost out to GEC.
  • 1968 International Computers and Tabulators was incorporated into ICL, which was owned 18% by Plessey and 18% by English Electric Co with the majority owned by ICT shareholders.
  • 1969 Acquired Painton company which made connectors and faders
  • 1969 At the behest of government, Plessey took over the numerical controls businesses of Ferranti and Racal (which was the Airmec-AEI business) and Diac. These were merged to form Plessey Controls.
  • 1971 Plessey installed its 100th TXE exchange, demonstrating the value of the 1961 merger. Plessey's defence and aircraft business were also prospering and the Swindon silicon chip business made a profit but the Numerical Controls business was losing money and substantial redundancies were required. Worldwide workforce reached 85,000.
  • 1972 Chairman Sir John Clark, needing to tackle the loss-making activities, initiated a reorganisation into 24 businesses, each operating as a separate profit centre, organised in nine divisions.
  • 1974 Plessey Co, Vicarage Lane, Ilford, Essex. Chairman — Sir John Clark; managing director — M. Clark. Group turnover (1972-73) £325 million. UK-based employees 60,000.
  • 1974 75,000 employees worldwide. Digital telephone exchange (TXE4) ready.
  • 1977 Post Office cutbacks hit Plessey’s business with 4800 workers made redundant. Threats to sell the semi-conductor businesses and microchip research centre (Caswell) were reversed by the Board.
  • 1981 First System X electronic exchange delivered to British Telecom.
  • 1984 First drop in profits for 8 years.
  • 1985 Increased semiconductor sales; focus on core businesses; sale of non-core businesses.
  • In December 1985 GEC launched a takeover bid for Plessey, valuing the group at £1.2 billion. Both Plessey and the Ministry of Defence (MoD) were against the merger as GEC and Plessey were the two largest suppliers to the MoD and, in many tenders, the only competitors.
  • 1986 GEC’s bid was referred to the Monopolies and Mergers Commission (MMC), whose report (August) advised against the merger although did favour a merging of telecommunications interests. The government blocked GEC's bid.
  • 1986 Plessey acquired Ferranti Semiconductors, creating Europe's largest semi-custom chip company. A new state-of-the-art silicon chip production facility near Plymouth was opened.
  • 1987 British Telecom (BT) decided to purchase System Y from Ericsson rather than System X from GEC and Plessey.
  • 1988 Plessey and GEC merged their telecommunications businesses in a joint venture GPT (GEC-Plessey Telecoms). This was the UK's leading telecommunications manufacturer but it had excess production capacity.
  • 1988 Plessey took over various defence suppliers in other countries to lessen its dependence on the UK Ministry of Defence and BT.
  • 1988 30,000 employees (not including GPT)
  • In 1988 GEC and Siemens AG set up a jointly held company, GEC Siemens plc, to launch a hostile takeover of Plessey. GEC Siemens' initial offer was made on 23 December 1988 valuing Plessey at £1.7 billion. Plessey again rejected the offer and again it was referred to the MMC. The original proposal envisaged joint ownership of all of Plessey's defence businesses, with GPT and Plessey's North American businesses split in the ratios 60:40 and 51:49 respectively. The level of GEC's involvement in the Plessey defence businesses was not likely to meet with regulatory approval. After reference to the MMC, in February GEC Siemens announced a new bid. The takeover was completed in September 1989.
  • 1989 Hansard recorded that Plessey had nearly 15,000 employees in the UK

UK Sites

  • Plessey Addlestone: Around 1965 Plessey, which had just taken over part of Decca to establish Plessey Radar, had to move out of Decca's premises at Chessington, and relocated to Addlestone. In the early 80's the main business became Plessey Displays, then later merged to become part of Plessey Naval Systems. Other businesses that existed alongside, or spun off, included Plessey Airports.
  • Plessey Caswell (Research): In 1945 (31st July) the farm was acquired by The Plessey Company from Major G. C. B. Bramwell
  • Plessey Christchurch: Prior to Plessey, this site was the Ministry of Defence Signals Research and Development Establishment (SRDE), until the MoD relocated it to RSRE at Malvern in the mid to late 70's
  • Plessey Exchange Works, (Cheapside, Liverpool): In 1959 Automatic Telephone and Electric Co, later Plessey, became the Prime Contractor for a new UK Air Defence System, under the name Plan Ahead and, from 1961, known as Project Linesman. To enable the system to be designed and built without too much information becoming public knowledge, a new factory called "Exchange Works" was built in Cheapside in Liverpool city centre, where young employees were granted exemption from conscription. At the heart of the system was the XL4 computer, based entirely on germanium transistors and using a computer language developed at Exchange Works in the 1950s and 1960s. During this period the company effectively became the world leader in computer design... unfortunately, this fact remained a close secret. The secure status of the factory attracted many other secret contracts and led to it becoming one of the major designers and manufacturers of cryptographic equipment. Exchange Works is now luxury flats.
  • Plessey Ilford:
  • Plessey Isle of Wight:
  • Plessey Liverpool (Edge Lane): Telephones
  • Plessey Northampton: Plessey Nucleonics, Plessey Interconnect, Plessey Connectors
  • Plessey Nottingham (Beeston): Telephones
  • Plessey Plympton: Plessey Semiconductors
  • Plessey Poole:
  • Plessey Roke Manor: Acquired the Roke Manor estate in 1956 and founded Roke Manor Research. Initially staffed by 28 engineers, the company undertook research into military communications systems.
  • Plessey Swindon: Known then primarily as a manufacturer of radio components, opened its factory in Kembrey Street, Gorse Hill, in 1940. By 1952, the Town Development Act led to the building of Cheney Manor Trading Estate which was to become an important part of the Plessey operation as the company chose the estate as the site of its new factories. By the beginning of the 1960s the number of Plessey workers in Swindon had grown to more than 5,000, and more expansion was to come with the opening of another Cheney Manor factory in 1962, providing a further 350 jobs in resistors. There were now three Cheney Manor sites - called Building 101, Building 102 and Building 103 - as well as the original and now substantial factory at Kembrey Street
  • Plessey Titchfield: In 1977, the site was Plessey Wound Components and Plessey Aerospace, with well over 1,200 employees. Since then the components side of the site was sold in 1980 leaving just the Aerospace business.
  • Plessey West Leigh (Havant):


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