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Events in Telecommunications History

1921

The first Rural Automatic Exchange (RAX) in this country was brought into service on 24 October at Ramsey, Huntingdonshire, in the Peterborough Telephone Area. It was a 40-line exchange, supplied by Siemens.

This was the first in a series of trials of exchange equipment intended to improve the telephone service to rural subscribers. Rural areas were until now served by small manual exchanges attended by caretaker operators. Exchanges with fewer than 20 subscribers did not normally give service at night or on Sundays, an obvious inconvenience. The Post Office eventually standardised on a GEC designed 100-line automatic exchange for rural areas known as RAX No. 5 in 1929.

A larger GEC design with 200 lines known as RAX No. 6 was introduced in 1931 and yet larger units with more facilities were adopted in 1937. These larger exchanges were suitable for both rural and urban areas and had facilities for dialling into, and receiving calls from main exchanges. Because the unit concept of construction was adopted, which allowed the exchange to be enlarged by the addition of further cabinets of equipment, they were known as UAX (Unit Automatic Exchange) Nos. 12, 13 and 14. The Post Office was now able to give rural communities a telephone service as good as that provided to urban subscribers.

Kiosk No. 1 was introduced, the first standard Post Office design and primarily intended for use as an open-air public call office in rural areas, later superseded by the No. 3. It was similar in design to the old wooden-box call offices, but was made up from three sections of reinforced concrete and fitted with a wooden door with the two sides and front containing glass panels. Once the kiosk had been constructed it could then be painted any colour to meet local conditions. The most distinctive feature of this kiosk was the spear-like finial on the roof, and roof signs were added on certain obscure kiosks. An initial contract had been placed with Somerville & Company in March 1920 for the supply of 50 kiosks at a price of £35 each - this was reduced to £15 in following years because of demand. Although the kiosk was quite successful, it was considered that a better design could be found. Eventually by 1931 the installation of the No. 1 in rural areas was discontinued.

Toll Exchange was opened at 3-5 Norwich Street, Fetter Lane, London, on 17 September, inaugurating the Toll System of call routing in London. The system was necessary because of heavy demands on the Trunk Exchange in GPO South in Carter Lane, EC4 (opened in 1904). As part of the new system, 350 direct short-distance trunk lines were diverted from GPO South to the new Toll Exchange by means of a new cable scheme, a major operation causing severe disruption in Ludgate Hill, and between the Old Bailey and Ludgate Circus. London subscribers saw a greatly improved service. Previously, making a trunk call involved what was known as 'delay working' where a subscriber booked long distance calls in advance and was later rung back by the operator when one of the trunk lines became available. Obviously, the greater the demand made on the exchange, the longer the wait. Under the new 'Toll' system subscribers were now able to ask the local operator for 'Tol' for calls to exchanges within the London Toll Area. They were then connected to the Toll operator who completed the call while the subscriber remained at the telephone. Later, as more automatic exchanges were introduced, the subscriber simply had to dial 'TOL' to be connected to the Toll operator.

The London Toll Area boundary was extended in 1923 and again in 1928, so that eventually Southampton, Portsmouth, Reading, Bedford, Colchester and the whole of Kent and Sussex were included. The system was later introduced to other large cities and remained in use until the late 1950s when, with the advent of STD, Toll was eventually phased out.

The Post Office Advisory Council was set up this year to advise the Postmaster-General and keep the Post Office in touch with the views of the business community and other users of its many services. Its membership consisted of representatives of a variety of interests in careful balance - political, national, social and functional.

The Research Section of the Post Office Engineering Department was moved from the City to a number of army huts at Dollis Hill. The Dollis Hill Research Station was later built on the same site in 1933.

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