The St Hilary transmitting station is a facility for

telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...

situated close to the village of St Hilary, Glamorgan in the

Vale of Glamorgan The Vale of Glamorgan ( cy, Bro Morgannwg ), often referred to as The Vale, is a county borough in the south-east of Wales. It borders Bridgend County Borough to the west, Cardiff to the east, Rhondda Cynon Taf to the north, and the Bristol C ...

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

, in the UK. It comprises a

guyed mast A guyed mast or guyed tower is a tall thin vertical structure that depends on guy lines (diagonal tensioned cables attached to the ground) for stability. The mast itself has the compressive strength to support its own weight, but does not ha ...

with

antennas In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies a ...

attached at various heights. The site was established in 1958 for Independent Television transmission on VHF. Transmissions from the site include

FM radio FM broadcasting is a method of radio broadcasting using frequency modulation (FM). Invented in 1933 by American engineer Edwin Armstrong, wide-band FM is used worldwide to provide high fidelity sound over broadcast radio. FM broadcasting is cap ...

DAB radio Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services. Types In digital broadcasting syst ...

and mobile telephone signals. It broadcasts

Heart Wales Heart South Wales is an regional radio station that broadcasts to South and West Wales from studios in Cardiff Bay. The station is owned and operated by Global Radio and forms part of the expanded Heart radio network of stations. Background Rea ...

on FM and DAB to the large parts of South Wales. Its broadcast areas include: St. Hilary, Cowbridge, Ystradowen, Miskin, Pontyclun, Bonvilston, St. Nicholas, Swansea, Llanelli, West of Barry, Pontypridd, Caerphilly, Mountain Ash, Llantrisant, Church Village and Talbot Green. The studios of the regional radio station

Nation Radio A nation is a community of people formed on the basis of a combination of shared features such as language, history, ethnicity, culture and/or society. A nation is thus the collective identity of a group of people understood as defined by those ...

are located on the site and its DAB transmissions to south-east Wales are made from the mast. Nation Radio also transmits from other sites, including on FM from nearby

Wenvoe Wenvoe ( cy, Gwenfô) is a village, community and electoral ward between Barry and Cardiff in the Vale of Glamorgan, Wales. Nearby are the Wenvoe Transmitter near Twyn-yr-Odyn and the site of the former HTV Wales Television Centre at Culverhouse ...

and from

Kilvey Hill Kilvey Hill ( Welsh: ''Mynydd Cilfái'' or ''Y Bigwrn'') is a hill in South Wales, to the east of Swansea. Kilvey Hill is high and is classed as a Sub Marilyn. The top of Kilvey Hill enjoys panoramic views of Swansea city centre, Swansea Do ...

near Swansea.

History

Construction

The plan by the

Independent Television Authority The Independent Television Authority (ITA) was an agency created by the Television Act 1954 to supervise the creation of "Independent Television" (ITV (TV network), ITV), the first commercial television network in the United Kingdom. The ITA exi ...

(ITA) to build a mast at the site was controversial (prompting a House of Lords debate in May 1957). This was due to its proximity to Rhoose Airport (now

Cardiff International Airport Cardiff Airport ( cy, Maes Awyr Caerdydd) is the only airport offering commercial passenger services in Wales. It has been under the ownership of the Welsh Government since March 2013, operating at an arm's length as a commercial business. Pa ...

), and ITA's initial plan for a mast on a site that itself is above sea level. Objections were noted, the mast height was eventually limited to and it was built by BICC in Summer 1957 to provide 405-line VHF television to south Wales and the West of England.

Transmission

Test transmissions commenced on 2 September 1957 on

Band III Band III is the name of the range of radio frequencies within the very high frequency (VHF) part of the electromagnetic spectrum from 174 to 240 megahertz (MHz). It is primarily used for radio and television broadcasting. It is also called high-b ...

channel 10 (199.75

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

) from antennas at 340 m above sea level and the station entered television broadcast service on that frequency in January 1958. The programming was initially provided by TWW. In 1965, Band III channel 7 (184.75 MHz) was added to the mast, transmitting from an antenna array sited about 20 m below the existing channel 10 array. This was to carry the programmes of the bilingual Teledu Cymru service that were already being provided by TWW in the rest of Wales, which in 1968 was replaced by Harlech Television (HTV Wales). From that point onwards, the channel 10 transmissions carried the English-language "General Service" (again, initially provided by TWW, and from 1968 by HTV). Channel 10's power output was decreased to 55 kW and the Wales-facing antennas were removed, though the power output towards the West of England remained about the same as it had been previously. In 1985, when 405-line TV closed, the site was re-engineered to remove the VHF television antennas. St. Hilary became just a telecommunications mast and remained so until October 2000 when

Real Radio Real Radio was a network of five regional radio stations broadcasting to North East England, North West England, Scotland, Wales and Yorkshire. Each station broadcast a mix of local and networked programming. On Tuesday 6 May 2014, the station ...

commenced FM Radio broadcasting from the site. In late 2000, DAB Digital Radio was added to the radio broadcasting repertoire initially transmitting the Cardiff & Newport multiplex on channel 11C, but with Swansea SW Wales on channel 12A commencing in February 2004. In 2006

Ofcom The Office of Communications, commonly known as Ofcom, is the government-approved regulatory and competition authority for the broadcasting, telecommunications and postal industries of the United Kingdom. Ofcom has wide-ranging powers acros ...

received a proposal for a new Rock-Orientated FM station to transmit from the site, but the licence was awarded to Xfm South Wales, now Nation Radio. Nation's studios are located at the foot of the St Hilary mast, but the station's Cardiff transmitter is a few miles away at Wenvoe.

Services

Analogue television

14 January 1958 - 15 February 1965

15 February 1965 - 3 January 1985

Analogue radio (VHF FM)

October 2000 - May 2014

May 2014 - present day

Digital Radio (DAB)

October 2000 - 31 January 2004

February 2004 - Present

References

External links

MB21's page on 405 TV to Wales and the West
{{DEFAULTSORT:Saint Hilary Transmitting Station Transmitter sites in Wales 1957 establishments in Wales Buildings and structures in the Vale of Glamorgan