Three Rock

Infobox Mountain
Name = Three Rock
Photo = Olympus Jan 2003 337w.jpg
Caption = Masts on Three Rock
Elevation = 450 m (1475 ft)
Location = Dublin, IRL
Range = Dublin Mountains
Prominence =
Coordinates = coord|53|15|N|6|14|W|type:mountain_scale:30000
Topographic
OSi "Discovery" 50
Type =
Age =
Last eruption =
First ascent =
Easiest route =
Grid_ref_UK =
Grid_ref_Ireland =
Listing =
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Language = English
Pronunciation =

Three Rock is a 450 metre mountain located in the Dublin Mountains, in the east of Ireland. It is a shoulder of the much less well known Two Rock, which is higher at 536 m. However, Three Rock projects out towards the southeastern part of the city, making it a valuable mast site. Originally known for the rocks at its summit, Three Rock is now most notable for its large collection of radio and television transmitters, with five separate towers on the mountain as of 2006.

Communication masts

RTÉ operate a large transmitter close to its peak at 450 metres above ordnance datum. The 300 ft (90 m) mast carries analogue UHF television to Dublin city and county, as well as FM and DAB radio. Other masts carry the majority of Dublin's local radio stations and some of the bigger pirate stations.

Transmissions began from Three Rock in June 1978, with RTÉ 1 and RTÉ 2 transmitting on UHF. Prior to 1978, Dublin had to rely on the Kippure television transmitter (which didn't satisfactorily cover some eastern and southern parts of the city) or a low power transmitter (now defunct) located at the RTÉ television centre itself (which served most of the districts not reached by Kippure)

The site is one of two RTÉ Network sites used for testing of new technology, including digital radio and digital television.

Trials

The Three Rock site has previously carried the test RTÉ DAB Multiplex and (along with Clermont Carn) is currently carrying the tests for Digital terrestrial television in Ireland.

Signals transmitted from Three Rock

Television

*RTÉ One, UHF channel 29 25 kW
*RTÉ Two, UHF channel 33 25 kW
*TV3, UHF channel 35 25 kW
*Digital terrestrial television test multiplex, UHF channel 54
*TG4, UHF channel 55 25 kW
*Digital terrestrial television test multiplex, UHF channel 58
*Digital terrestrial television test multiplex, UHF channel 61

Radio

"Frequencies in italics are proposed"
*Commercial DAB Multiplex, DAB channel 12A 20 kW
*RTÉ DAB Multiplex, DAB channel 12C 20 kW
*RTÉ Radio 1, FM radio 88.5 MHz 12.5 kW
*RTÉ 2fm, FM radio 90.7 MHz 12.5 kW
*Raidió na Gaeltachta, FM radio 92.9 MHz 12.5 kW
*"Future "Multi City" service, FM radio 94.9 MHz 1.5 kW" [http://www.bci.ie/documents/Final_Multi_City_Guide_April_07.doc]
*RTÉ Lyric FM, FM radio 96.7 MHz 5 kW
*Dublin's 98, FM radio 98.1 MHz 5 kW
*Today FM, FM radio 100.3 MHz 12.5 kW
*"Today FM, FM radio 101.8 MHz 0.5 kW (proposed replacement for 100.3)"
*Q102, FM radio 102.2 MHz 2 kW
*Spin 1038, FM radio 103.8 MHz 5 kW
*FM104, FM radio 104.4 MHz 5 kW
*Phantom 105.2, FM radio 105.2 MHz 2 kW
*Newstalk 106, FM radio 106 MHz 10 kW
*Dublin City FM, FM radio 103.2 MHz
*Raidió Na Life, FM radio 106.4 MHz 500W
*Dublin's Country Mix 106.8, FM radio 106.8 MHz 500W

Origin of the name

The mountain takes its name from the three 'rocks' that are visible from much of Dublin city and its suburbs, though there are actually five on the summit.

Several local clubs take their names from the mountain; a hockey club, the "Three Rock Rovers" soccer club, as well as "Three Rock Orienteering Club" [http://www.3roc.org] who mapped the area and have run regular orienteering competitions there since 1981.

A popular local monthly community magazine, the "Three Rock Panorama", defines the Three Rock area as comprising the Dublin suburbs of Dundrum, Ballinteer, Sandyford, Leopardstown, Stepaside, Kilternan, and the village of Glencullen, which is situated in the hills to the south of the mountain.

See also

*Wicklow Mountains
*Wicklow Way

External links

* [http://www.threerockmountain.com/ThreeRock.html Information about the mountain]

References