Events in telecommunications history
British Telecom's long distance network became totally digital on 3 July with the closure of Thurso electro-mechanical exchange in Scotland, completing the trunk lines modernisation beginning in 1985.
British Telecom's Worldwide Network Management Centre at Oswestry, Shropshire, was opened on 5 September at a cost of £4 million. The Centre monitored all of BT's System X exchanges (57 trunk and 373 local exchanges) and the company's three digital internal exchanges, identifying and remedying many problems before the customer became aware of them. Processors that controlled the exchanges generated data to the management floor at the Centre, where up to 30 network managers sat at specially designed consoles where they were fed continuously updated information on the number, destination and duration of calls made. From this data an overview of the digital network allowed efficient control and planning, protecting the network against the danger of congestion. Any potential trouble spots were highlighted on 25m (80ft) long video walls, at that time the largest in Europe, giving up to the minute pictures of how the networks were performing.
British Telecom announced the sale of its telephone manufacturing business based at Cwmcarn, Gwent to STC. Whilst owned by British Telecom, the manufacturing facility had been run by a wholly-owned subsidiary, BT Consumer Electronics.
This subsidiary also ran a telephone refurbishing activity, which was sold on 2 April 1991 to Fulcrum Communications Limited, an associated undertaking in which BT then held a 25 per cent equity interest.
These disposals ended 120 years of involvement of the Post Office and British Telecom involvement in the direct manufacture and refurbishment of telegraph and later telephone equipment. At its largest, the Post Office/British Telecom Factories Division consisted of eight factories around the country (three in London, three in Birmingham, one in Edinburgh and one in Cwmcarn) and employed 4,000 people.
BT Factories had been reorganised into two subsidiaries in 1985, BT Fulcrum Communciations and BT Consumer Electronics, to comply with terms of the BT Licence. These stated that any part of British Telecom involved in the production of telecommunications equipment had to be transferred to a subsidiary company by July 1986.
Under the agreement for the sale of the Cwmcarn facility, STC was to continue to supply the Vanguard telephone, which was thus the last telephone instrument to be manufactured by British Telecom.
British Telecom also gradually withdrew from involvement with cable operating companies as part of its general strategy of concentrating on its core business - providing network-related products and services to customers around the world. During the course of the year British Telecom sold its holdings in Thames Valley Cable, Ulster Cable, Aberdeen Cable Services Ltd., Swindon Cable and Coventry Cable.
The 100 millionth BT Phonecard was produced.
The biggest change to the London telephone numbering system since the introduction of All Figure Numbering took place on 6 May with the code change from 01 to 071 for inner London and 081 for outer London.
The code change was necessary because of the natural growth in demand for numbers and the proliferation of 'number hungry' equipment such as fax machines and PBXs with direct dialling facilities. Changing to 071 and 081 doubled the number of available London numbers. British Telecom had publicised the code changes over the previous year through television, radio, newspapers, poster sites, mailings and so forth. A code change party at Telecom Tower attended by several celebrities marked the actual changeover itself, which was broadcast live on television. To further celebrate the occasion British Telecom donated £1 million to the Royal Academy of Dramatic Art towards its new premises in central London.
There was a further code change in 1995.