Ferryside television relay station
Transmitted services -- Analogue and digital television
Table:
Frequency

UHF

kW

Service

System

471.25 MHz

21

0.023

BBC One Wales

PAL System I

489.833 MHz

23-

0.001

BBC Mux B

DVB-T

495.25 MHz

24

0.023

ITV1 Wales

PAL System I

513.833 MHz

26-

0.001

BBC Mux 1

DVB-T

519.25 MHz

27

0.023

BBC Two Wales

PAL System I

545.833 MHz

30-

0.005

Digital 3&4 Mux 2

DVB-T

551.25 MHz

31

0.023

S4C

PAL System I

578.000 MHz

34

0.005

SDN Mux A

DVB-T

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The hertz ( symbol : Hz ) is the derived unit of frequency in the International System of Units ( SI ) and is defined as one cycle per second . It is named after Heinrich Rudolf Hertz , the first person to provide conclusive proof of the existence of electromagnetic waves . Hertz are commonly expressed in multiples : kilohertz ( 103 Hz , kHz ) , megahertz ( 106 Hz , MHz ) , gigahertz ( 109 Hz , GHz ) , terahertz ( 1012 Hz , THz ) , petahertz ( 1015 Hz , PHz ) , exahertz ( 1018 Hz , EHz ) , and zettahertz ( 1021 Hz , ZHz ) . Some of the unit 's most common uses are in the description of sine waves and musical tones , particularly those used in radio- and audio-related applications . It is also used to describe the clock speeds at which computers and other electronics are driven . The units are sometimes also used as a representation of energy , via the photon energy equation ( E=hν ) , with one hertz equivalent to h joules .
BBC One Wales is a television channel operated by BBC Cymru Wales . It is the Welsh variation of the UK-wide BBC One and is broadcast in Wales from Broadcasting House in Cardiff . BBC One Wales broadcasts around three hours of non-news programmes for Wales each week alongside six hours a week of national news for Wales from Wales Today .
Phase Alternating Line ( PAL ) is a colour encoding system for analogue television used in broadcast television systems in most countries broadcasting at 625-line / 50 field ( 25 frame ) per second ( 576i ) . It was one of three major analogue colour television standards , the others being NTSC and SECAM . Almost all of the countries using PAL are currently in the process of conversion , or have already converted standards to DVB , ISDB or DTMB . This page primarily discusses the PAL colour encoding system . The articles on broadcast television systems and analogue television further describe frame rates , image resolution and audio modulation .
DVB-T is an abbreviation for Digital Video Broadcasting - Terrestrial ; it is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in February , 1998 . This system transmits compressed digital audio , digital video and other data in an MPEG transport stream , using coded orthogonal frequency-division multiplexing ( COFDM or OFDM ) modulation . It is also the format widely used worldwide ( including North America ) for Electronic News Gathering for transmission of video and audio from a mobile newsgathering vehicle to a central receive point . It is also used in the US by Amateur television operators .
ITV Wales and West , previously known as Harlech Television ( HTV ) , refers to the Independent Television franchise area until 31 December 2013 , licensed to a broadcaster by the regulator Ofcom . There is no channel , past or present , named ITV Wales and West . The licence relates to a 'dual region ' , meaning that the franchise area was divided into two regions , each of which had to be served by distinct and separate ITV programme services , as more fully defined within the licence . Today , those services are known as ITV Cymru Wales and ITV West Country ( since ITV West and ITV Westcountry merged into a single region ) . They are provided by ITV plc which owns and operates the two services through its subsidiary ITV Broadcasting Ltd. From January 2014 , the dual-region licence was split in two , with ITV Cymru Wales for Wales and ITV West Country covering the West of England . Both licences remain held by ITV Broadcasting Ltd and the legal names of the former HTV companies have not yet been changed again . The National Library of Wales archives now store 200,000 ITV ( HTV ) film and video items dating from 1958 .
The British Broadcasting Corporation ( BBC ) is a British public service broadcaster . Its headquarters are at Broadcasting House in Westminster , London . It is the world 's oldest national broadcaster , and the largest broadcaster in the world by number of employees . It employs over 22,000 staff in total , more than 16,000 of whom are in public sector broadcasting . The total number of staff is 35,402 when part-time , flexible , and fixed-contract staff are included . The BBC is established under a Royal Charter and operates under its Agreement with the Secretary of State for Digital , Culture , Media and Sport . Its work is funded principally by an annual television licence fee which is charged to all British households , companies , and organisations using any type of equipment to receive or record live television broadcasts and iPlayer catch-up . The fee is set by the British Government , agreed by Parliament , and used to fund the BBC 's radio , TV , and online services covering the nations and regions of the UK . Since 1 April 2014 , it has also funded the BBC World Service ( launched in 1932 as the BBC Empire Service ) , which broadcasts in 28 languages and provides comprehensive TV , radio , and online services in Arabic and Persian . Around a quarter of BBC 's revenue comes from its commercial subsidiary BBC Studios ( formerly BBC Worldwide ) , which sells BBC programmes and services internationally and also distributes the BBC 's international 24-hour English-language news services BBC World News , and from BBC.com , provided by BBC Global News Ltd . In 2009 , the company was awarded the Queen 's Award for Enterprise in recognition of its international achievements . From its inception , through the Second World War ( where its broadcasts helped to unite the nation ) , to the 21st century , the BBC has played a prominent role in British life and culture .
BBC Two Wales is the national variation of BBC Two for BBC Cymru Wales . It is broadcast to Wales from Broadcasting House in Cardiff . The channel can opt out from the main BBC Two schedule to show Welsh made programming , however this is used less frequently than in the past . From 5 November 2001 until 2 January 2009 , BBC Two Wales was the name of the analogue service broadcasting to Wales , and was the brand used on the digital service outside the broadcasting hours used by BBC 2W . BBC 2W was the sister channel to BBC Two Wales , until the Digital Switchover saw the end of analogue broadcasts in Wales . The specific BBC 2W service was closed down and the BBC Two Wales brand used .
Digital 3 & 4 is a consortium consisting of ITV plc , STV Group plc and the Channel Four Television Corporation , which operates a multiplex broadcasting from a number of transmitter sites in the United Kingdom , carrying television and radio channels , together with interactive services , from both ITV and Channel 4 . Unlike other multiplexes , the regional ITV broadcaster has control over which services are to be broadcast on their allotted amount of the capacity , leading to small regional differences across the country .
S4C ( Welsh pronunciation : [ ˌɛs ˌpɛdwar ˈɛk ] , from the Welsh Sianel Pedwar Cymru , meaning Channel Four Wales ) is a Welsh-language free-to-air television channel . The first television channel to be aimed specifically at a Welsh-speaking audience , S4C is the fourth-oldest television channel in the United Kingdom after BBC One , ITV and BBC Two . As of 2017-2018 , S4C had an average of 131 employees . S4C 's headquarters is based in Carmarthen , at the University of Wales Trinity Saint Davids creative and digital centre , Yr Egin . It also has regional offices in Caernarfon and Cardiff . When first established , the channel - initially broadcast on analogue television - was bilingual ( Welsh and English ) outside peak hours , with English-language content consisting of the simultaneous or deferred transmission of programmes from Channel 4 ( analogue reception of which was unavailable in most of Wales ) . When digital terrestrial television arrived several years later , S4C added a second , full-time Welsh-language channel called S4C Digidol ( digital ) on 1 November 1998 . With the completion of the digital switchover in Wales on 31 March 2010 which made English-language Channel 4 available across Wales as S4C 's bilingual analogue channel closed , and what had been S4C Digidol became the default S4C channel , available on Freeview and pay television , and broadcasting entirely in Welsh . S4C does not commission programming in English , but when English is used on the channel it is left untranslated . Moreover , the channel includes an English subtitle track available for some programmes , which can be accessed using their television set 's remote control .
S4C Digital Networks ( SDN ) is a company that operates one of the six multiplexes of channels on digital terrestrial television in the United Kingdom . It is now wholly owned by ITV plc .