Portishead Radio

Portishead Radio (callsign GKA) was a radio station in England that provided worldwide maritime communications and long-range aeronautical communications from 1928 until 2000. It was the world's largest and busiest radiotelephony station. In 1974, there were 154 radio operators who handled over 20 million words per year.

The station's control centre, which was based at Highbridge, near Burnham-on-Sea, opened in July 1928. It was constructed by Marconi Wireless Telegraph Company and operated by the General Post Office (GPO). Following the privatisation of the post office in 1981, the station was operated by British Telecommunications PLC (now known as BT Group PLC).

The main transmitting station, which was remotely operated, originally consisted of a large array of radio masts at nearby Portishead Downs; it was replaced by a single radio mast at Clevedon. It was used until 1972. Various other remotely operated transmitting stations, including Devizes, Rugby, Leafield, Chipping Ongar, and Dorchester, were also used.

By 1936, the station had a staff of 60 radio officers who handled over 3 million words of radio traffic per year.

The station played a vital role during World War II in maintaining communications with the British merchant navy and with patrol aircraft in the North Atlantic. During the war, all communications with ships were one-way in order to avoid revealing the ships' locations to the enemy. The station was short staffed because many staff were away on secondments to various government services, such as operating other radio stations and training new radio officers to work in naval convoys. In 1943, the workload was so great that a Royal Navy officer and 18 telegraphists were brought in from HMS Flowerdown, a Naval Shore Wireless Service station near Winchester.

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