Английская Википедия:Emley Moor transmitting station

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Шаблон:Short description Шаблон:Use British English Шаблон:Use dmy dates Шаблон:More citations needed Шаблон:Infobox transmitter

The Emley Moor transmitting station[1] is a telecommunications and broadcasting facility on Emley Moor,[1] Шаблон:Convert west of the village centre of Emley,Шаблон:Refn in Huddersfield, West Yorkshire, England.

It is made up of a Шаблон:Convert[1] concrete tower and apparatus that began to transmit in 1971. It is protected under UK law as a Grade II listed building. It is the tallest freestanding structure in the United Kingdom,[1][2] and 25th tallest tower in the world.[1] It was the seventh tallest freestanding structure and was fourth tallest tower in the European Union before Brexit.[1] When built it was the sixth tallest freestanding structure in the world after the Ostankino Tower, the Empire State Building, 875 North Michigan Avenue (known as The John Hancock Center), the Berliner Fernsehturm and Tokyo Tower.[3]

The tower's current official name, The Arqiva Tower, is shown on a sign beside the offices at the base of the tower, but it is commonly known just as "Emley Moor Mast".[1]

In 2021, the antenna was replaced, to accommodate frequency changes for mobile phone use, by a shorter antenna of Шаблон:Convert but the structure still remains the tallest freestanding structure in the United Kingdom.

History

Emley Moor has been a transmission site since the earliest days of commercial television in the UK. The present concrete tower is the third antenna support structure to have occupied the site.

The first permanent transmitter built there was for ITV, covering much of the north of England. It had a Шаблон:Convert lattice tower, which provided limited coverage. This original Шаблон:Convert lattice tower was erected in 1956 to provide Independent Television broadcasts to the Yorkshire area. It entered service on 3 November 1956, transmitting Granada Television programmes on weekdays, and ABC TV programmes at weekends.

Second mast and collapse

In 1964, in anticipation of colour PAL transmissions set to begin in 1966, the original Шаблон:Convert lattice tower was replaced by a taller Шаблон:Convert guyed mast, identical to the structure at Belmont transmitting station in Lincolnshire. The dismantled lattice tower was rebuilt at Craigkelly transmitting station.[4] Yorkshire Television commenced broadcasting from the Emley Moor transmitter following the reorganisation of the ITV franchises on 29 July 1968.

The guy-supported tubular mast was constructed from curved steel segments to form a Шаблон:Convert diameter tube, Шаблон:Convert long, and was surmounted by a lattice section Шаблон:Convert tall, and a capping cylinder, bringing the total height to Шаблон:Convert. At the time of its construction, it was one of the tallest human-made structures in the world. It was designed by British Insulated Callender's Cables (BICC), and manufactured by EMI, and built by J. L. Eve Construction.

Its ropes weighed Шаблон:Convert, made by British Ropes, with steel from Steel, Peech and Tozer of Templeborough in South Yorkshire. The column weighed Шаблон:Convert and had 375 segments, with steel from United Steel Companies at Scunthorpe in northern Lincolnshire.[5]

The cylindrical steel mast was regularly coated in ice during the winter, and large icicles formed on the guy wires, placing them under great strain. During winter, ice often fell from the guy-wires. For this reason, amber warning lights on the tower operated when ice was a hazard, and notices were posted on the fence adjacent to Jagger Lane, below the guy wire crossings.[6]

On 19 March 1969, a combination of strong winds and the weight of ice that had formed around the top of the mast and on the guy wires caused the structure to collapse. The duty engineer wrote the following in the station's log book, demonstrating that failure of the structure was completely unexpected:

  • Day [shift]: Lee, Caffell, Vander Byl [surnames]
  • Ice hazard - Packed ice beginning to fall from mast & stays. Roads close to station temporarily closed by Councils. Please notify councils when roads are safe (!)
  • Pye monitor - no frame lock - V10 replaced (low ins). Monitor overheating due to fan choked up with dust- cleaned out, motor lubricated and fan blades reset.
  • Evening [shift]: Glendenning, Bottom, RedgroveШаблон:Efn [surnames]
  • Шаблон:Convert Mast :- Fell down across Jagger Lane (corner of Common Lane) at 17:01:45. Police, I.T.A. HQ, R.O., etc., all notified.
  • Mast Power Isolator :- Fuses removed & isolator locked in the "OFF" position. All isolators in basement feeding mast stump also switched off. Dehydrators & TXs switched off.
Файл:Emley Moor Mast Wreckage.jpg
Wreckage of the Emley Moor Mast, which collapsed in March 1969, strewn across fields.

The collapse left sections of twisted mast strewn over the transmitter site, and across the junction of Common Lane and Jagger Lane, and the surrounding fields. Although a falling stay cable cut through the roof of a local church[7] and across the transmitter site buildings, no one was injured. It completely disabled the BBC2 UHF transmitter and the ITV VHF transmitter, leaving several million people without service. BBC1 VHF television transmissions continued from Holme Moss. The Independent Television Authority (ITA) owned a collapsible emergency mast, Шаблон:Convert tall, which was moved to Emley from the Lichfield transmitting station so that some service could be restored. ITV signals were restored to 2.5 million viewers within four days. The BBC provided a mobile mast on an outside broadcast van to restore a restricted BBC2 colour service within two days. The ITA bought a larger temporary mast from a Swedish company. A crew of Polish riggers were hired, and a Шаблон:Convert mast was erected in under 28 days at a cost of Шаблон:£ (equivalent to £Шаблон:Inflation million in Шаблон:Inflation/year). This mast could hold only one set of antennae, so many viewers in outlying areas still could not receive colour programmes. The taller mast was brought into service on 16 April. Some weeks later, the BBC erected a Шаблон:Convert mast, improving coverage.

Файл:Vortex-street-animation.gif
Vortex shedding behind a circular cylinder. In this animation, the flows on the two sides of the cylinder are shown in different colours, to show that the vortices from the two sides alternate, which can build an oscillating motion in the cylinder. Courtesy, Cesareo de La Rosa Siqueira.

The accumulation of ice was believed to have caused the collapse, but a committee of inquiry attributed it to vortex shedding which occurred over a five year period of low but steady wind speed, enhanced during periods of high wind speed.[6] Damping modifications, including hanging Шаблон:Convert of steel chains within each structure, were made to similar masts at Belmont and Winter Hill. None of the modified masts have collapsed.

A section of the collapsed tower was converted for use as a racing control tower at Huddersfield Sailing Club.[8]

New tower

After the setting up of temporary masts, erection of the current concrete tower began in 1969. It was not built on the site where the original mast had stood, but slightly to the south-east at Шаблон:Coord. UHF (625-line colour) transmissions commenced on 21 January 1971, and the older VHF (405-line black and white) system became operational on 21 April 1971. Local residents did not wish to see another mast on Emley Moor, and a departure from usual designs was called for. The new structure consists of a tapered cylindrical pillar, Шаблон:Convert tall, constructed of reinforced concrete, and is topped by a Шаблон:Convert steel lattice mast which carries the antennae.

Structure

The structure is a tapered, reinforced concrete tower. It is the tallest freestanding structure in the United Kingdom at a height of Шаблон:Convert,[1] Шаблон:Convert taller than The Shard. Reaching the tower room at the top of the concrete structure at Шаблон:Convert involves a seven-minute journey by lift. The antenna structure above it is a further Шаблон:Convert tall. The mast's foundations penetrate Шаблон:Convert into the ground, and the whole structure, including foundations, weighs Шаблон:Convert. The tower was designed by Arup. When built, it was the third-tallest freestanding structure in Europe, after the Ostankino Tower at Шаблон:Convert, and the Fernsehturm Berlin (current height Шаблон:Convert). The top of the tower is Шаблон:Convert above sea level, due to the site's elevated position on the eastern edge of the Pennines. The tower is not open to the public. There was an observation area off the main road that runs past it, but as of 25 February 2018, this seems to be closed.[9] The tower has a top-floor interior equipment area at a height of Шаблон:Convert, which is accessible to people.[10]

Файл:Emley Moor Mast.png
The tower at night

In 2002, English Heritage granted the tower Grade II listed building protection under UK law, being the lowest and most common of three categories, for meeting its criteria of significant architectural or historic interest.[2][1]

Ownership

The tower is currently owned by Arqiva, previously the Independent Broadcasting Authority Engineering section, privatised as NTL Broadcast.

Broadcast details

Emley Moor tower broadcasts six digital television multiplexes, three digital radio ensembles, and two independent local radio stations (Capital Yorkshire and Heart Yorkshire), over an area of approximately Шаблон:Convert. It is the main station for 57 relays and repeaters throughout Yorkshire and the surrounding counties. In July 2007, it was confirmed by Ofcom that Emley Moor would remain a B group transmitter after digital switchover (DSO).

The area is important for RF, radio frequency transmission, and from the foot of the structure, both Holme Moss and the Moorside Edge transmitter are visible. They are within a ten-mile (16 km) radius, and are located to the southwest and west-northwest, respectively.

Its television coverage area is one of the largest in the UK; covering most of Yorkshire and parts of the East Midlands including Leeds, Sheffield, York, Chesterfield, Worksop and Mansfield. Some transmissions can be received in Greater Manchester across the Pennines due to the height of the antenna on the tower and the powerful signal.

Repairs and alterations

Over the years, the concrete structure has been updated to reflect the changing nature of communications and technology. At the top and bottom of the tower, supporting structures have been attached to accommodate dishes and aerials.

The BBC reported in July 2006 that for up to two weeks, it would broadcast analogue and digital signals at a lower power than usual, or shut down between 09:00 and 15:00 BST on weekdays from late July until 4 August, to allow aircraft warning lights to be fitted and repairs carried out. Repairs were estimated to affect around five million homes; however, a spokesperson for National Grid Wireless announced that the work had been scheduled around major events.[11]

Digital UK reported in April 2010 that the transmitter would undergo work in preparation for the digital switchover (DSO) in 2011. Disruption to some or all Freeview services was expected to last for around two months, during which time a reserve transmitter would continue to broadcast the five main analogue channels.[12] The work was then reported to be continuing into September due to "poor weather conditions and complex engineering issues".

In March 2018, a temporary Шаблон:Cvt mast was erected so that work could be undertaken on the main tower's transmitting arrays without interrupting transmissions,.[13] The temporary mast was due to be removed by the end of 2021. However, it was not until summer 2023 that work got underway to dismantle it, carried out by Turmbau Steffens & Nölle GmbH of Berlin.[14]

Channels listed by frequency

Файл:Emley Moor mast at sunset - geograph.org.uk - 497294.jpg
Emley Moor's distinctive tapering form on the moorland

Analogue radio (FM)

frequency kW[15] service
105.1 MHz 2.55 Capital Yorkshire
106.2 MHz 2.35 Heart Yorkshire

Digital radio (DAB)

frequency block kW[15] operator
216.928 MHz 11A 10 Sound Digital
222.064 MHz 11D 8.5 Digital One
225.648 MHz 12B 10 BBC National DAB
229.072 MHz 12D 5 BBC Radio Leeds

Шаблон:Col-begin Шаблон:Col-2

Digital television (DVB-T/DVB-T2)

frequency UHF kW operator system
Шаблон:UK DVB-T 33 174 COM4 (SDN) DVB-T
Шаблон:UK DVB-T 36 174 COM5 (ARQ A) DVB-T
Шаблон:UK DVB-T 39 5 LTVmux DVB-T
Шаблон:UK DVB-T 41 174 PSB3 (BBC B) DVB-T2
Шаблон:UK DVB-T 44 174 PSB2 (D3&4) DVB-T
Шаблон:UK DVB-T 47 174 PSB1 (BBC A) DVB-T
Шаблон:UK DVB-T 48 174 COM6 (ARQ B) DVB-T

Шаблон:Col-2

Before switchover

Шаблон:No2frequency Шаблон:No2UHF Шаблон:No2kW Шаблон:No2operator Шаблон:No2system
Шаблон:UK DVB-T 39 4 BBC B (Mux HD) DVB-T2
Шаблон:UK DVB-T 40- 10 Digital 3&4 (Mux 2) DVB-T
Шаблон:UK DVB-T 43- 5 SDN (Mux A) DVB-T
Шаблон:UK DVB-T 46- 10 BBC (Mux B) DVB-T
Шаблон:UK DVB-T 49- 4 Arqiva (Mux D) DVB-T
Шаблон:UK DVB-T 50- 10 Arqiva (Mux C) DVB-T
Шаблон:UK DVB-T 52+ 10 BBC (Mux 1) DVB-T

Шаблон:Col-end

Analogue television

At Emley Moor, BBC Two analogue closed on 7 September 2011, and ITV Yorkshire temporarily moved onto its frequency at the time to allow the BBC A MUX to launch in its place. The remaining four analogue services closed on 21 September 2011, when the remaining digital multiplexes were allowed to transmit with increased power.

Шаблон:No2frequency Шаблон:No2UHF Шаблон:No2kW Шаблон:No2service
Шаблон:UK System I 37 870 Channel 5
Шаблон:UK System I 41 870 Channel 4
Шаблон:UK System I 44 870 BBC1 Yorkshire
Шаблон:UK System I 47 870 Yorkshire
Шаблон:UK System I 51 870 BBC2 Yorkshire

Relays

Below is a list of transmitters that relay Emley Moor.

Digital television

transmitter kW BBC-A BBC-B D3&4 SDN ARQ-A ARQ-B Local Pol. A.G.
Addingham 0.005 43 46 40 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Armitage Bridge 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Batley 0.003 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Beecroft Hill 0.2 37 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a 39 V B K
Blackburn in Rotherham 0.002 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Bradford West 0.003 39 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Brockwell 0.002 45 39 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Calver Peak 0.05 45 39 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Chesterfield 0.4[r 1] 31 29 37 43 46 40 Шаблон:N/a V K
Cleckheaton 0.002 29 37 31 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Conisbrough 0.002 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Cop Hill 0.2 25 28 22 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Copley 0.002 29 37 31 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Cornholme 0.008 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Cowling 0.003 42 49 45 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Cragg Vale 0.005 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Cullingworth 0.003 39 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Dronfield 0.002 39 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Edale 0.002 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Elland 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Grassington 0.012 23 26 30 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Hagg Wood 0.007 39 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Halifax 0.1 24 27 21+ Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Hasland 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Headingley 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Hebden Bridge 0.05 25 28 22 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Heyshaw 0.1 39 45 42 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Holmfield 0.004 29 37 31 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Holmfirth 0.005 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Hope 0.002 28 25 22 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Idle 0.05 23 30 26 32 35 34 Шаблон:N/a V A K
Keighley 2 40 46 43 29 31 37 Шаблон:N/a V K
Keighley Town 0.002 23 29 26 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Kettlewell 0.026 42 39 45 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Longwood Edge 0.008 29 37 31 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a H A K
Luddenden 0.012 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Lydgate 0.002 21 27 24 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Millhouse Green 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Oughtibridge 0.008 23 30 26 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Oxenhope 0.04 25 28 22 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Primrose Hill 0.006 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Ripponden 0.012 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Shatton Edge 0.2 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Sheffield 1[r 2] 27 21+ 24 42 45 39 35 V K
Skipton 2 49 42 45 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B E
Skipton Town 0.003 24 21+ 27 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Stocksbridge 0.002 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Sutton-in-Craven 0.002 23 30 26 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Tideswell Moor 0.05 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Todmorden 0.1 39 42 45 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Totley Rise 0.016 33 48 36 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Walsden 0.01 40 46 43 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V B K
Walsden South 0.002 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Wharfedale 0.4 25 28 22 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Wheatley 0.3 32 35 34 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K
Wincobank 0.002 29 37 31 Шаблон:N/a Шаблон:N/a Шаблон:N/a Шаблон:N/a V A K

Шаблон:Reflist

Other structures of comparable height

Taller structures
Smaller structures

See also

Шаблон:Portal

Notes

Шаблон:Notelist

References

References

Шаблон:Reflist

Notes

Шаблон:Reflist

External links

Шаблон:Commons category

Шаблон:Television transmitters in the UK Шаблон:Emley Moor VHF 405-line Transmitter Group Шаблон:Supertall


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