The British Broadcasting Company became the British Broadcasting Corporation on 1 January.
A regular public transatlantic telephone service from London to New York using long-wave radio transmission on a wavelength of 5,000 metres (60kHz) was begun on 7 January at 1.45 pm. The original tariff was £15 for three minutes, reduced to £9 the following year.
The first director exchange in Europe was opened at 270 High Holborn and was known as Holborn Tandem. It provided a switching centre for exchanges in the Director Area which were not in direct communication. (The director technique allowed the Strowger automatic system to be used in large cities, using a three letter exchange code in front of the number, and was introduced in 1922.)
Cast iron kiosks were introduced (Kiosk No. 2), designed by Sir Giles Gilbert Scott. The installation of this kiosk was confined to London (where many can be seen today) and some large provincial towns following a competition held in 1924.
The No. 4 kiosk was introduced. It was first proposed in 1923 and a prototype was erected in Bath in 1926. In addition to the telephone it contained facilities for buying stamps and posting letters. The standard No. 4 kiosk was designed by the Post Office Engineering Department on the basis of the successful No. 2 and received final approval in 1927. It was constructed in cast iron and was considerably larger than any of the other types. Painted vermilion outside and a flame colour inside, it gained the nickname of 'The Vermilion Giant'. Only 50 of these kiosks were ever made, at an original cost of £50 6s 9d each. They were intended to be a miniature Post Office, located where no such facilities existed or where expense prevented a sub-post office from being built. Unfortunately these kiosks were unsuccessful. Many people complained about the noise of the stamp machine while they were using the telephone, and the rolls of stamps in the machine tended to become soggy in damp weather. For these reasons, and because of the high unit cost, the Post Office decided in 1935 that no further kiosks of this type would be installed.
The London Toll system was divided between Toll 'A' and Toll 'B' exchanges because of the increase in Toll traffic which made it necessary to divide the direction of originated traffic. Toll 'A' manual exchange opened on 3 December on the 5th Floor, GPO South, Carter Lane, EC4 to handle traffic outwards. The old exchange at Fetter Lane, opened in 1921, became known as Toll 'B' and handled traffic into London .
An international time signal was broadcast throughout the world from Rugby Radio Station. A joint development with the Admiralty and Board of Trade, it was intended to assist mariners. The time signals were generated from the Royal Greenwich Observatory.
In 1949 quartz clocks provided by the Post Office replaced the mechanical pendulum clocks in the Greenwich Time Signal (GTS) generating apparatus at the Royal Observatory. These clocks continued in use until 1967, when caesium atomic standards were introduced.
Rugby still transmits the Greenwich Time Signal, which is derived from the National Physical Laboratory's atomic resonance standard. The laboratory is now the UK's national centre for time - its atomic clocks generate the UK's time standard, which is made available via transmissions from Rugby Radio Station. The BBC's "pips" are derived in part from the same signal (the BBC has been responsible for generating the 'pips' since 5 February 1990 when it assumed the role from the Royal Greenwich Observatory).
Telephone service was established with Austria, Denmark, Norway and Sweden.