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36-522: It comprises a 260.7-metre (855 ft) guyed mast with antennas attached at various heights. The average height above sea level is 384 metres (1,260 ft) for the television antennas. It is owned and operated by Arqiva . The site serves an estimated 1.5m listeners (0.63m households) in the South West of England, and 1.3m listeners (0.54m households) in Wales. The original 230 m (750 ft) mast at

72-492: A mast radiator antenna (for VLF , LF , MF ). In the latter case, the mast needs to be insulated from the ground . Guyed radio masts are typically tall enough that they require several sets of guy lines, 2 to 4, attached at different heights on the mast, to prevent them from buckling. An exception to multiple guys was the Blaw-Knox tower , widely used during the 1930s, whose distinctive wide diamond ( rhomboidal ) shape gave it

108-499: A 46 m guyed lattice mast carrying the aerials at the top. This structure was built on a 440 m hill known as Gilwern Hill overlooking the towns of Gilwern and Abergavenny in Monmouthshire , South Wales. The band III VHF television feeds were provided off-air from St. Hilary and Wenvoe , both near Cardiff . In 1973 the site was enhanced to transmit UHF analogue colour television . The UHF television feed came via

144-452: A broader geometric base allows for a mast much taller than the free-standing basement tower, and the integration of tower and mast should be considered in all facets of construction and maintenance. Abergavenny transmitting station The Abergavenny transmitting station was originally built by the IBA in 1969 as a relay for BBC and ITV VHF 405-line analogue television. It consists of

180-445: A free-standing base, in most cases of concrete or of lattice steel, with a guyed mast on the top. The anchor base of the guyed mast can be on the top of the tower or on the ground. Partially guyed towers are typically used when a very high tower for FM and TV transmission is required, while also carrying antennas for directional radio services at a much lower height. In such cases the antennas for directional radio services are mounted on

216-572: 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 217.7 m (714 ft) stayed mast (Wenvoe "C") on 14 June 2006 and it was completed in September 2006. This carried

252-569: A two-hop route from Wenvoe, via the Ebbw Vale repeater. The 405-line VHF television service closed across the UK in 1985, but according to the BBC's and IBA's transmitter list and the BBC's internal "Eng. Inf." magazine, Abergavenny was due to close early - in the third quarter of 1982. Currently, the hill's transmitters provide UHF digital terrestrial TV, VHF FM radio and DAB digital radio. The transmission station

288-439: Is currently owned and operated by Arqiva . Freeview digital terrestrial TV was not available from this transmitter before the digital switchover process began at Wenvoe, with the first stage taking place on 31 March 2010. The second stage was completed on 27 April 2010. Abergavenny transmitter initially provided BBC and ITV 405-line VHF television to the mid Usk valley area which is strongly shielded by local hills from both

324-470: Is some overspill into Bristol and the West Country, though service quickly drops off after Bristol. Digital Radio is transmitted from Wenvoe at high power and is designed to cover South Wales and the West Country. Guyed mast A guyed mast is a tall thin vertical structure that depends on guy lines (diagonal tensioned cables attached to the ground or a base) for stability. The mast itself has

360-415: The masts of sailing vessels, guyed towers, and as the main tower of heavy equipment such as cranes , power shovels , draglines , and derricks , the simplest of which is the gin pole . Guyed masts are frequently used for radio masts and towers . The mast can either support radio antennas (for VHF , UHF and other microwave bands ) mounted at its top, or the entire structure itself can function as

396-404: The 2,063 feet (629 m) KVLY-TV mast near Blanchard, North Dakota , USA. The mast on heavy equipment such as a crane is its main supporting tower, typically of trussed steel construction. Wire rope guys typically led back to the crane's base stabilize it and support its ability to bear significant shear loads while lifting. A partially guyed tower is a tower structure which consists of

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432-489: The 700 MHz Band, on 22 June 2020, the Arqiva COM8 multiplex was switched off permanently on UHF Channel 56. Wenvoe used a rather erratic set of frequencies at the start, bandplan changes agreed in 1978 were brought into play in 1981. BBC Radio 1, BBC Radio 2, BBC Radio 3, BBC Radio 4 and Classic FM broadcasts from Wenvoe are intended to be for South Wales and the West Country, though the signal reaches much further due to

468-542: The UHF TV channels, but to be received with the same aerial-group. The QAM constellations and number of carriers were changed around 2002 after the collapse of ITV Digital as the service was taken over by the Freeview consortium. Analogue BBC Two Wales on channel 51 closed after 45 years of service, and HTV Wales was moved from channel 41 to that channel for what would be its final month of service. Multiplex 1 from channel 30

504-474: 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

540-566: The UK. Being in Wales, Wenvoe transmitted the S4C variant. The 405-line BBC1 Wales service on Band III from Wenvoe was discontinued early. The off-air 405-line relays at Abergavenny , Carmarthen and Llanelli had been decommissioned the previous year. This left Llandrindod Wells (and Wenvoe's indirect off-air relay at Llanidloes ) and Kilvey Hill as the last surviving 405-line BBC Wales transmitters classed as relays of Wenvoe. 405-line transmissions from Kilvey Hill and Llanidloes were due to shut in

576-570: The Wenvoe Transmitter on 6 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. The second mast came into service carrying the BBC Wales service. The first UHF 625-line television service started from Wenvoe. This required the installation of a Band V antenna at

612-662: The Wenvoe transmitter and the St. Hilary transmitter. 625-line UHF television in colour came to Abergavenny. This was with the station acting as an indirect off-air relay of Wenvoe. The 405-line VHF TV services were shut down after 15 years. From then onwards TV transmissions were on UHF only. Channel 4 launched across the UK on 1 November 1982. Abergavenny (being in Wales) transmitted the S4C variant. The UK's digital switchover commenced at Abergavenny on 31 March 2010. Analogue BBC Two Wales on channel 45

648-446: 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

684-405: The analogue signals whilst Wenvoe "A" was to be structurally improved and extended by 23 metres (75 ft). 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

720-457: The compressive strength to support its own weight, but does not have the shear strength to stand unsupported or bear loads. It requires guy lines to stay upright and to resist lateral (shear) forces such as wind loads . Examples include masts on sailing vessels, towers for telecommunications, meteorology, and masts on cranes, power shovels, draglines, and derricks, starting with the simple gin pole . The principle applications of guyed masts are

756-422: The digital switchover at Wenvoe required a third phase to allow time for channels 42 and 45 to be cleared at Ridge Hill . At this point, Arq A and SDN were shifted fully into the group with a power increase: As a side-effect of frequency-changes elsewhere in the region to do with clearance of the 800 MHz band for 4G mobile phone use, Wenvoe's "Arqiva B" multiplex was moved from channel 49 to channel 39. This

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792-404: The guyed mast to a guyed mast on plain ground, and the construction of the free-standing basement tower does not differ much from a tower of the same height without a mast. The guyed mast of such constructions is usually of lesser height than basement tower. Partially guyed towers in which at least one basement of the guy anchors is on the ground are more rare. The placement of guy basements across

828-471: The high ERP and use of omni-directional antenna systems. Radio Cymru and Radio Wales have the same radiation pattern but different effective radiated powers. Radio Wales has a lower ERP to prevent it interfering with BBC Radio Cornwall on the same frequency. There is overspill allowing stereo listening for R. Wales & R. Cymru in the West Country. Nation Radio is broadcast at low power to ensure sufficient penetration of Cardiff, Newport and Bridgend. There

864-524: The hut is much smaller than the mast radiator. Such constructions include the Mühlacker radio transmitter and the Ismaning radio transmitter . Partially guyed towers can be divided into two types, depending on the placement of the guy anchors. Guyed masts on skyscrapers or wider towers are often guyed on the roof of the free-standing basement structure. In such cases, there is no major constructive difference of

900-548: 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 191 m (625 ft) 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 (214.75 MHz), and entered service on 9 February 1964. The 405-line transmitter for this service

936-469: The second quarter of 1983, leaving Llandrindod Wells to continue alone until January 1985. The 405-line VHF television system was shut down across the whole UK, and until the start of digital television services, Wenvoe's TV output was 625-lines on UHF only. This was the initial roll-out for digital television using the DVB-T system. The transmitter frequencies and power outputs were chosen not to interfere with

972-400: The shear strength that it only required one set of guys. Guyed masts are sometimes also used for measurement towers , to collect meteorological measurements at certain heights above ground level. Sometimes they are used as pylons (transmission towers), although their usage in agricultural areas is problematic because anchor foundations handicap ploughing. The tallest guyed tower is currently

1008-403: 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. It remained on air until the closure of 405-line television in 1985. In 1955 VHF FM radio was added to

1044-412: 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

1080-569: The top of the free-standing part of the tower, while the guyed mast on its top carry the FM and TV antennas. They can be also used in order to upgrade small stable towers (like watertowers) with a long antenna mast for FM and TV broadcasting. However their use is rare, and they exist chiefly in certain European countries. Note that mast radiators which stand atop an antenna tuning hut ( a.k.a. helix building) are not considered partially guyed towers, because

1116-686: The top of the mast, replacing the 1952 Band I antenna that had originally been sited there. The new Band I antenna was brought into service on 8 December 1964, and was sited immediately below the Band V antenna and above the Band II antenna. This put it in close proximity with the fixings of the top deck of guy wires, requiring some careful engineering so as not to affect the radiation pattern adversely. † Monochrome initially, colour TV service started September 1967. † Monochrome initially, colour production at BBC One Wales started 9 July 1970. Channel Four launched across

Wenvoe transmitting station - Misplaced Pages Continue

1152-449: Was closed early, in 1983. 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

1188-403: Was first to close, and ITV Wales was moved from channel 49 to channel 45 for its last month of service. The new BBC A mux started up in 64-QAM and at full power (i.e. 200 W) on channel 49 which had just been vacated. The remaining three analogue TV services were closed down. Digital multiplexes took over their original frequencies at full power and in 64-QAM encoding mode from the start. As

1224-518: Was re-used for Multiplex C, freeing Multiplex C's old allocation at channel 43- All remaining analogue television was shut down after 40 years of service. The pre-switchover low-power digital transmissions (apart from Arqiva A and SDN) were upgraded to full power and configured to 64QAM and 8k carriers, with frequency changes and with new names for the multiplexes: † High-definition channels; BBC One HD, BBC HD, ITV1 HD and S4C Clirlun using DVB-T2 transmission, coded with MPEG4 100 kW ERP. Unusually,

1260-471: Was renamed BBC A and moved to channel 41+ (which had just been vacated by analogue HTV Wales). In addition to the power increase to 100 kW ERP, it was reconfigured to 64QAM and 8k carriers, which resulted in a service area similar to the old analogue transmissions but with much more bandwidth available than Multiplex 1 ever had. For the duration of the switchover, all the channels carried on Multiplex B were duplicated on this new PSB1 multiplex. Channel 30

1296-578: Was to allow channel 49 to be taken over at a future date by the Mendip transmitter. Following changes in the 700 MHz Band on 15 May and 6 June 2019, the Arqiva COM7 multiplex is transmitted on UHF Channel 55 and the COM8 multiplex is on UHF Channel 56. These multiplexes carry additional HD services. The Local TV Multiplex is on UHF Channel 37 and commenced antenna tests around 1 December 2013. Following changes in

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