Valves, radios and the first transatlantic call.
Following the outbreak of the First World War the facilities of Western Electric were made available to the government for the military effort and its factories produced munitions, field telephones, mine and submarine detectors. The British branch of Western Electric distanced itself from its American counterpart and began to develop radio technologies. The war also resulted in a large increase in female employees.
“Where in 1914 you saw Jack Jones you now see Cissy Brown at the capstan lathe in the screw machine and fuse departments… Girls work on ledgers in the accounts department. Some make cable reels and cases, some are on inspection work which, but a short time since, would have been deemed impossible by some and unmaidenlike by others”.
G C Goodburn, an employment manager quoted in Western Electric News ('Power of Speech' by Peter Young, 1983)
Valves developed in the early 1900s, were invaluable as signal amplifiers and it was discovered that in combination they would act as an electronic switch. At the end of the war Western Electric’s laboratories in New York brought out the first designs for cable repeaters incorporating valve amplifiers. This development gave Western Electric a technical lead on which to build a major business in line transmission. Valves were also essential to radio production and in 1922 a site was established at New Southgate, housing a new radio department. This involved the introduction of new equipment and processes such as glass working, heat treatment of metal parts, electric spot welding and vacuum pumping. The same year saw the establishment of the British Broadcasting Company (later Corporation) by various companies including Western Electric and radio broadcasts began in London.
In January 1923 Western Electric conducted the first one way transatlantic telephone call by radio when the President of AT&T spoke to a group of Western Electric employees and the press, assembled in a wooden hut on the New Southgate site. This was a two hour call for which dinner jackets were worn!
In 1925 the International Telephone and Telegraph Corporation (ITT) took over all Western Electric’s interests outside the United States and Western Electric Ltd in England was renamed Standard Telephones and Cables Ltd. The company underwent a restructure with the North Woolwich factories being responsible for transmission, power lines and telephone lines, and New Southgate being responsible for telephone apparatus and radio. Two new research laboratories were also set up to generate new telecommunication developments, a British laboratory in Hendon broadly concentrating on advances in cables and a lab in Paris. In the same year STC introduced the first water-cooled valves in Europe. These were used in standardised broadcasting transmitters installed at stations around the world.
STC won a contract to design and supply a radio telephone transmitter for Rugby for transatlantic (long wave) radio. With a power of 200kW, the Rugby transmitters were 500 times as strong as an ordinary broadcast, and the 800-foot-high masts employed 10 miles of cable. This long wave radio-telephone transmitter was used for the opening of the commercial telephone service between London and New York in 1927.
To overcome the problem of cross-talk (noise bleed between lines) STC introduced a new sort of cable utilising a newly developed material, polythene. These ‘coaxial cables’ consisted of an outer strip of copper encircling and insulated from an inner core and were ideal for use on telephone trunk routes.
In 1931 STC gave the world’s first public demonstration of ‘micro-ray’ (microwave) communication between Dover and Calais. Telephone messages were sent and received and documents transmitted by facsimile. This new technology was put to use as a link in the air-traffic control circuit between London and Paris and in the following year, Britain's first ultra-short wave radio telephone link was set up by the Post Office across the Bristol Channel, spanning a distance of 13 miles. The engineer Alec Reeves had worked on microwave transmission and had started to experiment with combining the different signals of telegraphy and telephony. In 1938 Reeves patented the idea of pulse code modulation, the digital representation of analogue signals. Though it was not to be realised for another 20 years, PCM was to herald a communications revolution.
The New Southgate site more than doubled its manufacturing space to over 250,000 feet during the 1930s and by 1939 around 3500 men and 2500 women were employed by STC at this site alone.
Top image: man at work in the valve shop at New Southgate, 1932 (NAEST 211/2/6/3 B.9919)
Bottom image: parabolic reflector at St Margaret’s Bay, Dover, for first public demonstration of microray (microwave) transmission, 3 April 1931 (NAEST 211/2/30/2/1 D.7242)