Start Point transmitting station

The Start Point transmitting station is a broadcasting facility at Start Point, Devon, owned by National Grid Wireless. The site is just north-west of the Start Point lighthouse.

The station currently transmits a single broadcast: BBC Radio 5 Live on 693 kHz.

History

1930s

In 1935 the BBC started looking for transmitter sites to improve radio coverage in Devon, Dorset and Cornwall. After investigating 23 sites and carrying out extensive tests, two sites were selected: Start Point and Clevedon in Somerset. Start Point came on air on June 14th, 1939 using an ST&C type C100 100 kW transmitter on 1050 kHz, and broadcast the West of England regional programme. A directional aerial array was used to avoid wasting power over the English Channel and to enhance the signal to the east and west. It consisted of two 450 ft stayed lattice masts, one being a mast radiator and the other a parasitic reflector. Both masts had a break at 310 ft to allow for the insertion of a loading coil.Pawley, Edward (1972), "BBC Engineering 1922-1972", London, BBC, pp. 97-8, 106, 238-9, 254, 257, 326, 348. ISBN 0-563-12127-0] Shacklady, Norman and Ellen, Martin (2003), "On Air - A History of BBC Transmission", Wavechange Books, pp. 6, 10, 13, 28. ISBN 0-9544077-1-7] [http://www.bbceng.info/Operations/transmitter_ops/Reminiscences/start_point.htm Frost, Stuart (2004), "Start Point’s special role following D Day"] . Prospero magazine, July 2004.]

The station obtained power from two 11 kV mains feeders and a 400 kW diesel alternator.

The building design followed L. Rome Guthrie's earlier work at the Brookmans Park transmitting station. By agreement, the BBC obtained copyright in the Brookmans Park elevation drawings and was able to follow them, with changes to allow for building size, for several other sites.

The station closed on September 1st, 1939, in anticipation of the outbreak of war between Britain and Germany two days later.

World War II

In October 1939 BBC Research engineers experimented with horizontally-polarised transmissions at Start Point. The idea was to see if broadcasts could be made without providing enemy aircraft with a navigational radio beacon. A horizontal dipole antenna was suspended between the two masts. The test was reasonably successful and between February 18th and September 15th, 1940 regular transmission were carried in the evenings, on 877 kHz, of what became the "Forces' Programme".

A Marconi SWB18 short wave transmitter (Sender 22) was added to the station to carry the Home Service on 6075 kHz, from January 20th 1940. This was intended to provide coverage where the mediumwave signals were poor, and to provide an emergency backup to the landline distribution network in case of major disruption. This transmitter also carried the European Service (Norwegian) at certain times.

In October 1940, the station began to transmit the European Service on 1050 kHz. This also used a horizontally-polarised antenna. The transmitter's power was increased to 180 kW, with a consequent increase in audio distortion.

Post 1945

The station carried the West of England Home Service on 977 kHz from July 29th, 1945. In 1967 the Home Service became Radio 4. By 1978, Start Point had moved to 1052 kHz. On November 23rd 1978, there was a major reorganisation of the medium wave band in Europe, and from that date the station transmitted Radio 1 on 1053 kHz.Television and Radio Stations 1978. BBC Engineering Information booklet.]

References

External links

* [http://tx.mb21.co.uk/gallery/start-point.php The Transmission Gallery: Start Point]