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The Wenvoe transmitting station is a facility for broadcasting and telecommunications situated close to the village of Wenvoe in the Vale of Glamorgan, Wales, in the UK. It comprises a guyed mast with antennas attached at various heights. The mast (with extension completed February 2008) plus the Main UHF antenna on top now gives a structure height of 260.7 metres (855 ft). The average height above sea level is 392 metres for the television antennas. It is owned and operated by Arqiva. ==History== The original mast at the site was built in 1952 by the BBC to provide 405-line VHF television to south Wales and the west of England. The station broadcast on Band I channel 5 (66.75 MHz) from 15 August 1952 using its reserve transmitters, and from 20 December 1952 with its main high-power transmitters.〔Pawley, Edward. 1972. ''BBC Engineering 1922-1972'' p. 374. BBC Publications, ISBN 0-563-12127-0〕 It remained on air until the closure of 405-line television in 1985. In 1955 VHF FM radio was added to the mast, carrying the BBC's Home Service. This was followed by the addition of the Light Programme in 1956 and the Third Programme in 1959. In 1963 a second mast was built alongside the existing structure. This was in order to carry the new BBC Wales 405-line TV service on Band III VHF channel 13, and entered service on 9 February 1964.〔http://downloads.bbc.co.uk/rd/pubs/reports/1964-29.pdf〕 It too remained on air until the closure of 405-line television in 1985. On 12 September 1965, a 625-line black and white television service BBC2 became available from Wenvoe on UHF. This new transmitter was capable of colour broadcasting from the start and was used for unannounced colour TV engineering test-transmissions from that point onwards. In September 1967 BBC2 officially launched a colour TV service from Wenvoe, a few months after BBC2 Crystal Palace and others had launched the UK's first colour broadcasting in July of that year. In 1970 UHF 625-line colour television was introduced for BBC1 and ITV Wales (HTV Wales. S4C was added later when it launched in 1982. In 1985, when 405-line TV closed, the site was re-engineered and both of the existing masts were taken down. They were replaced by a brand new mast (to be known as Wenvoe "A"), which is the structure currently in place at the site. Wenvoe "B" is a self-supporting telecommunications mast nearby. The VHF FM antennas were upgraded from the old horizontally polarised slot antennas to new mixed polarisation antennas, and the transmitter power was doubled. The new analogue Channel 5 was launched in 1997, but this was never transmitted from Wenvoe. It was presumably thought that the 125 kW transmitter at Mendip would serve a satisfactory number of homes in Wenvoe's service area. At the time, many homes within range of Mendip already had aerials pointing at it so as to receive the English-only Channel 4 rather than the bilingual English/Welsh S4C transmitted from Wenvoe. Work began on a new temporary stayed mast (Wenvoe "C") on 14 June 2006 and it was completed in September 2006. This carried the analogue signals whilst Wenvoe "A" was to be structurally improved and extended by . Wenvoe "A" was fitted with a new high-power digital antenna and a full reserve antenna. New high-power digital TV transmitters were installed in the buildings, which would allow Wenvoe "A" to broadcast all six main digital TV multiplexes, as well as a seventh currently proposed by OFCOM 〔()〕 after the analogue signals were switched off in 2010. This mechanical upgrade was completed by the summer of 2009 and Wenvoe "C" was dismantled starting in late August 2009. Wenvoe's analogue BBC Two service was switched off on 3 March 2010 and the remaining analogue TV services were switched off on 31 March 2010. At this point, Wales had officially completed its switchover to digital TV services. BBC Radio Wales commenced broadcasting from the Wenvoe Transmitter on the 6th of December 2011 at 10:39. This replaced the low power VHF Transmitter on the Wenallt Hill which also carried BBC Wales VHF programme on 103.9 MHz to South East Wales up to that point. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wenvoe transmitting station」の詳細全文を読む スポンサード リンク
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