Divis
Encyclopedia
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
and area of sprawling moorland
Moorland
Moorland or moor is a type of habitat, in the temperate grasslands, savannas, and shrublands biome, found in upland areas, characterised by low-growing vegetation on acidic soils and heavy fog...
to the north-west of Belfast
Belfast
Belfast is the capital of and largest city in Northern Ireland. By population, it is the 14th biggest city in the United Kingdom and second biggest on the island of Ireland . It is the seat of the devolved government and legislative Northern Ireland Assembly...
in County Antrim
County Antrim
County Antrim is one of six counties that form Northern Ireland, situated in the north-east of the island of Ireland. Adjoined to the north-east shore of Lough Neagh, the county covers an area of 2,844 km², with a population of approximately 616,000...
, Northern Ireland
Northern Ireland
Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...
. The mountain is 478 m (1,568 ft) tall, making it the highest of the Belfast Hills. It extends north to the Antrim Plateau and shares its geology; consisting of a basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
ic cover underlain by limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
and lias
Early Jurassic
The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...
clay.
Only recently have the Divis area and its surrounding mountains been handed over to the National Trust
National Trust for Places of Historic Interest or Natural Beauty
The National Trust for Places of Historic Interest or Natural Beauty, usually known as the National Trust, is a conservation organisation in England, Wales and Northern Ireland...
; from 1953 to 2005, it was under the control of the Ministry of Defence
Ministry of Defence (United Kingdom)
The Ministry of Defence is the United Kingdom government department responsible for implementation of government defence policy and is the headquarters of the British Armed Forces....
. It was also used as a training area for the British Army
British Army
The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...
. It might have been released earlier, but due to the period of unrest known as the Troubles
The Troubles
The Troubles was a period of ethno-political conflict in Northern Ireland which spilled over at various times into England, the Republic of Ireland, and mainland Europe. The duration of the Troubles is conventionally dated from the late 1960s and considered by many to have ended with the Belfast...
, the British Government and military viewed the area as a useful vantage point, overlooking Belfast.
Divis Transmitter
Divis transmitter is the main high-power UHF and BBC National FM/DAB station that serves County Antrim and parts of County Down.Sited just outside Belfast, it is the primary UHF/FM main station in Northern Ireland and was originally the country's main BBC 405-line television transmitter, coming into operation in this capacity in July 1955. As such, it was the first permanent television transmitter to be established within Ireland.
Although one of three UHF main stations in Northern Ireland, it is the only one to feature a stayed mast, the other stations at Brougher Mountain
Brougher Mountain transmitting station
Brougher Mountain transmitting station is a major transmitting station in Northern Ireland. It is located between County Tyrone and County Fermanagh, on top of a 317-meter high hill called Brougher Mountain....
and Limavady both utilising smaller self-supporting towers. Stayed masts are however located at the UHF relay stations at Londonderry and Strabane (respectively former BBC and ITA 405-line relays) and at Black Mountain, the former ITA 405-line main station and current transmitter of Channel 5 that is sited adjacent to Divis. It is owned and operated by Arqiva
Arqiva
Arqiva is a telecommunications company which provides infrastructure and broadcast transmission facilities in the United Kingdom and Republic of Ireland. The present company, with headquarters located at Crawley Court in the village of Crawley, Hampshire, was formed by National Grid Wireless...
.
The Divis station is located in a range of hills directly overlooking Belfast to the west, in an area which for many years was controlled by the Ministry of Defence, until it was sold in 2004 to the National Trust and subsequently opened to the public. It is sited between the peaks of Divis Mountain and Black Mountain and is ironically closer to the latter than the transmitter that is named after it.
Television history
Divis was opened by the BBC on 21 July 1955 as their permanent 405-line Band I transmission facility serving Northern Ireland. It superseded the temporary station at Glencairn, which was one of two transmitters (the other being Pontop Pike) to be rushed into operation on 1 May 1953, in time for the televised Coronation of Queen Elizabeth II. Although the BBC had by this time already obtained the Divis site, the need to construct the long access road was the primary factor preventing its immediate use for a provisional installation.Divis was designated as a medium-power transmitter, on which type of installation the second phase of BBC Band I stations were based. In this respect, Divis was grouped with permanent installations at Meldrum, North Hessary Tor, Pontop Pike, Rowridge, Sandale and Tacolneston. Transmissions from Divis were on VHF Channel 1 at a peak output of 35 kW vision e.r.p.
In due course, a number of relay stations were established across Northern Ireland to enhance coverage from Divis, most notably at Brougher Mountain in County Fermanagh, the latter being the site of a future UHF main station.
In the meantime, the Independent Television Authority (ITA) built their equivalent 405-line VHF Band III station close to Divis. Located at Black Mountain quarry, less than two miles to the south-west, this came into operation on 31 October 1959 and utilised a taller 750-ft mast.
Divis however became the UHF main station for Belfast and surrounding area with BBC2 the first regular service commencing 18 March 1967. Colour UHF transmitters for BBC1 and ITV came into operation in September 1970.
Both this site and Black Mountain are perhaps not surprisingly (bearing in mind the area history) dual ring-fenced for enhanced security.
It has since been made public that the current transmitter mast (152.5 m) at Divis will be removed and replaced by a brand new guyed steel mast (192.7 m). This means for a period of time there will be two broadcast masts at the site in preparation for the digital switchover in the Ulster region in October 2012
By way of its extensive transmitter bases, Divis contributes significantly to the telecommunications network for much of Northern Ireland.
Analogue television services broadcast on the following channel numbers:
| Frequency | UHF | kW | Service |
|---|---|---|---|
| 471.25 MHz | 21 | 500 | Channel 4 Channel 4 Channel 4 is a British public-service television broadcaster which began working on 2 November 1982. Although largely commercially self-funded, it is ultimately publicly owned; originally a subsidiary of the Independent Broadcasting Authority , the station is now owned and operated by the Channel... |
| 495.25 MHz | 24 | 500 | UTV UTV UTV is a television channel based in the UK region of Northern Ireland. The channel is the Channel 3 or Independent Television licensee for Northern Ireland and is operated by UTV Limited, a wholly owned subsidiary of UTV Media.- Terrestrial :* Analogue: Normally tuned to 3 * Freeview : 3... |
| 519.25 MHz | 27 | 500 | BBC Two Northern Ireland |
| 551.25 MHz | 31 | 500 | BBC One Northern Ireland BBC One Northern Ireland BBC One Northern Ireland is the national variation for BBC Northern Ireland of the network BBC One service broadcast by the BBC. The service is broadcast in Northern Ireland from Broadcasting House in Belfast... |
| 775.25 MHz | 59 | N/A | TG4 TG4 TG4 is a public service broadcaster for Irish language speakers. The channel has been on-air since 31 October 1996 in the Republic of Ireland and since April 2005 in Northern Ireland.... |
All of the above channels, except TG4, broadcast at a power of 500 kW. As well as providing direct reception for most TV viewers in Northern Ireland, all the other analogue transmitters in the province source their output, either directly or indirectly, from Divis. TG4, a channel operated by a state-owned body of the Republic of Ireland
Republic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...
, is broadcast at a very low power and not relayed to any other transmitters. Channel 5 is broadcast from the nearby Black Mountain transmitting station
Black Mountain transmitting station
The Black Mountain transmitting station is a broadcasting and telecommunications facility, situated on land 301 metres above Ordnance Datum to the west of the city of Belfast, in Northern Ireland . It includes a guyed steel lattice mast which is 228.6 metres in height...
.
Digital television services broadcast on the following channel numbers, and with the following powers:
| Frequency | UHF | kW | Operator |
|---|---|---|---|
| 489.8 MHz | 23- | 2.3 | SDN S4C Digital Networks SDN is a company that operates Multiplex A, one of the six groups of channels on digital terrestrial television in the United Kingdom... (Mux A) |
| 513.8 MHz | 26- | 2.3 | BBC BBC The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff... (Mux B) |
| 538.0 MHz | 29 | 2.3 | BBC (Mux 1) |
| 569.8 MHz | 33- | 2.3 | Digital 3&4 Digital 3&4 Digital 3&4 is a consortium consisting of regional Channel 3 companies and Channel 4 Television Corporation, which operates a multiplex broadcasting from a number of transmitter sites in the UK, carrying television and radio channels from both ITV and Channel 4; however three per-cent of the... (Mux 2) |
| 578.2 MHz | 34+ | 1.6 | Arqiva Arqiva Arqiva is a telecommunications company which provides infrastructure and broadcast transmission facilities in the United Kingdom and Republic of Ireland. The present company, with headquarters located at Crawley Court in the village of Crawley, Hampshire, was formed by National Grid Wireless... (Mux D) |
| 690.0 MHz | 48 | 2 | Arqiva (Mux C) |
FM
FM broadcasting
FM broadcasting is a broadcasting technology pioneered by Edwin Howard Armstrong which uses frequency modulation to provide high-fidelity sound over broadcast radio. The term "FM band" describes the "frequency band in which FM is used for broadcasting"...
radio service broadcast on the following frequencies and with the following powers:
| Frequency | kW | Service |
|---|---|---|
| 90.1 MHz | 250 | BBC Radio 2 BBC Radio 2 BBC Radio 2 is one of the BBC's national radio stations and the most popular station in the United Kingdom. Much of its daytime playlist-based programming is best described as Adult Contemporary or AOR, although the station is also noted for its specialist broadcasting of other musical genres... |
| 92.3 MHz | 250 | BBC Radio 3 BBC Radio 3 BBC Radio 3 is a national radio station operated by the BBC within the United Kingdom. Its output centres on classical music and opera, but jazz, world music, drama, culture and the arts also feature. The station is the world’s most significant commissioner of new music, and its New Generation... |
| 94.5 MHz | 250 | BBC Radio Ulster BBC Radio Ulster BBC Radio Ulster is one of two Northern Irish BBC radio stations, the other being BBC Radio Foyle located in the city of Derry. BBC Radio Ulster is located at Broadcasting House in the Ormeau Avenue area of Belfast city centre... |
| 96.0 MHz | 125 | BBC Radio 4 BBC Radio 4 BBC Radio 4 is a British domestic radio station, operated and owned by the BBC, that broadcasts a wide variety of spoken-word programmes, including news, drama, comedy, science and history. It replaced the BBC Home Service in 1967. The station controller is currently Gwyneth Williams, and the... |
| 99.7 MHz | 250 | BBC Radio 1 BBC Radio 1 BBC Radio 1 is a British national radio station operated by the British Broadcasting Corporation which also broadcasts internationally, specialising in current popular music and chart hits throughout the day. Radio 1 provides alternative genres after 7:00pm including electronic dance, hip hop, rock... |
| 101.9 MHz | 250 | Classic FM Classic FM (UK) Classic FM, one of the United Kingdom's three Independent National Radio stations, broadcasts classical music in a popular and accessible style.-Overview:... |