Cable television (originally known as "piped TV") in Ireland first started in 1963, when several companies, including the state broadcaster, RTÉ, started relaying the United Kingdom's terrestrial television channels in some cities and larger towns. Today, all Irish cities and many larger towns have cable networks.

Technology Ireland's cable television networks are now entirely digital. However, in many areas, Virgin Media Ireland carried a small number (approximately 16) analogue channels alongside digital services until 2019; while the two independent cable operators in Cavan and Longford carried significantly more analogue channels into the early 2020s.

The legacy analogue cable television services provided unencrypted PAL System I television channels. Frequency plans varied from place to place, and channels were carried in VHF Band I, Band III, Hyperband, and sometimes UHF Band IV.

In the past, additional encrypted premium analogue channels were also available. To view these channels a set-top box was required. Cablelink / NTL Ireland used Cryptovision, while some other companies, notably Cork Multichannel, used Jerrold (General Instrument) scrambling systems.

Cork City and other areas cabled by Cork Multichannel Television required a Jerrold (General Instrument) set top box for all channels. The entire Cork analogue cable network was encrypted from the late 1980s onward. The Cork network also carried more channels than other cable networks in Ireland at that time.

When digital cable was launched in Cork, Virgin Media Ireland rapidly swapped analogue set top boxes for digital boxes and then shut down the analogue service entirely. The network carried analogue terrestrial channels, RTÉ1, RTÉ2, TV3 and TG4 in some parts of the network until 2018. This means that Cork became the first city in Ireland to have an exclusively digital cable network.

For analogue cable in Ireland, there was no set frequency plan. Most cable networks for analogue used harmonically related carriers (carrier frequencies of exact 8 MHz multiples). Some cable networks such as Limerick used Irish terrestrial channel alignments or even a mixture of the two-channel plans.

The Virgin Media Ireland digital cable network operates using DVB-C, with a set top box required to view their television services. The two independently owned cable networks in Cavan and Longford use DVB-T and do not require a set top box.

Digital networks have far more sophisticated trunking systems. The five main cities (Dublin, Cork, Galway, Limerick, and Waterford), along with towns like Longford, Dungarvan, Clonmel, Thurles, Kilkenny etc. now enjoy state of the art Hybrid fibre-coaxial networks which are used to deliver a myriad of services, including digital television, broadband DOCSIS 3.0, and cable telephony services.

Overhead cables (strung between buildings rather than utility poles, as used in the United States) are common in areas constructed before the foundation of the local cable firm, or where the cable firm did not have a construction agreement with the builders; underground cables are more common in developments build post-1985.

History

In the early years of television, Irish viewers had access to the BBC via signals coming from Northern Ireland and Wales. By 1959, Northern Irish viewers had access to one public service broadcaster (BBC) and one commercial broadcaster (Ulster Television). The Secretary of the Department of Posts and Telegraphs in the Republic, Leon Ó Broin, had tried to progress the idea of an Irish channel since 1953; this new medium coming from Northern Ireland spurred the Irish government into action.Horgan, J. (2001) Irish Media: A Critical History Since 1922, 1st ed., London and New York, Routledge: p77 Teilifís Éireann began broadcasting on 31 December 1961. During these years many Irish radio listeners where listening to BBC Radio so the interest in BBC Television would continue; some had been watching since 1949 via spillover signals. The first cable service from RTÉ in 1963 was RTÉ Relays; these tests were in preparation for the building of the Ballymun apartment blocks, which were built during these early years of RTÉ Television. RTÉ Relays opted to provide their service with the BBC and Ulster Television (later, the Cablelink company would also provide HTV from Wales).

The first city outside Dublin to build a purpose-built cable television network under the new 1974 regulations was Waterford, which initially delivered service to some 6,000 homes in 1974. It supplied an analogue service to an estimated 14–16,000 homes in Waterford City, along with almost 5,000 cable broadband customers, including VoIP (Voice over Internet Protocol) telephony services.

Other cities followed suit, but not until the 1980s. First Cork in 1981, then Limerick in 1983, and Galway by 1985. However, due to legislation regarding the use of microwave links at the time, companies were forced to lay untold kilometres of cable to get from the headend to the city.

The cable connecting Cork to the Comeragh Mountains was 100 km (60 miles) in total: the longest cable television route ever built in Europe. The Casey Cablevision company of Dungarvan, County Waterford held the Irish record previously, with a 25 km (16 mile) line connecting to the Comeragh Mountains headend. Cork Communications (Cork Multichannel TV) had initially built a head-end in the Knockmealdown Mountains, but reception there was less than satisfactory and a deal was done after a few months in 1982 to use Casey Cablevision's headend.

The majority of major cable systems in Ireland now use fibre optics, however some smaller systems still use a mixture of microwave links, UHF antennae, and direct satellite feeds to local headends.

By the 1980s, cable television was well-established as the most popular multi-channel television reception system in Ireland. In addition to providing Irish and British terrestrial television, Irish CATV systems generally began adding additional services during the 1980s as English-language services started to appear on European satellites that were receivable in Ireland. This greatly enhanced the number of channels available to customers. Property developers also began to pre-wire new homes for cable service where it was available. By the end of the decade, cable television was more popular than both direct reception of UHF television from the UK and satellite television.

Timeline of when Irish cities and towns received cable

1971 - Dublin City 1975 - Waterford, Celbridge, Arklow, Dundalk, Longford and Cavan 1976 - Glenties, Enniscorthy and New Ross 1978 - Boyle, Sligo and Mullingar 1979 - Carlow, Greystones, Rush and Ashbourne 1980 - Navan Town 1981 - Clonard Estate, Dundrum, Athlone, Dungarvan, Cork City and Naas 1982 - Swords 1983 - Bagenalstonwn, Maynooth and Limerick City 1984 - Portlaoise, Clane, Tullamore, Kilkenny Town and Portarlington 1985 - Buncrana, Carrigaline, Ballina, Clonmel and Nenagh 1986 - Galway City, Donegal Town and Newbridge

Further towns such as Thurles, Tipperary, Tullow, Ennis, Castlebar, and Birr were cabled during the late 1980s.

The provision of cable television was regularly debated in the Irish parliament (Dáil Éireann) which set out details of years of cable licence operations in the country.

Multichannel

Long before any coaxial cable had been laid for the distribution of television in Ireland, the Irish were enjoying multi-channel television. Even before Teilifís Éireann had begun to broadcast, Irish viewers were watching the BBC and ITV. The BBC signal was available to 40% of the population in the Republic by the late 1950s.Horgan, J. (2001) Irish Media: A Critical History Since 1922, 1st ed., London and New York, Routledge: p80 Many had already installed outdoor aerials to get signals from Northern Ireland or Wales. Not all of the country could get access to these British signals, so they were introduced to television by the new Irish television service Teilifís Éireann; by the time the 1960 Broadcasting Act had been produced, around 50,000 television set had been sold in Ireland.Horgan, J. (2001) Irish Media: A Critical History Since 1922, 1st ed., London and New York, Routledge: p88 During this time Ireland experienced economic growth and the beginnings of Community Antenna Television (CATV) or cabled television broadcasts. RTÉ set up their relays service for viewers in Ballymun providing both the BBC and Ulster Television on their service known as RTÉ Relays.Report of the Cable Systems Committee, 1984 Even before the advent of Sky Digital in Ireland and later FTA UK Satellite, over 75% of households had ITV (UTV and/or HTV).

Laying Ireland's cable

There were two prevailing reasons for cable. The attraction of the British channels and hence more choice, and better reception for many people, analogue terrestrial signals covered about 90% of the population. Cable companies around Dublin (such as RTÉ Relays, Marlin Communal Aerials Ltd., and Phoenix Relays Ltd.) provided the three main British broadcasters at the time (later they would also provide Channel 4 and satellite channels).Flanagan, P. (1994) Cable TV in Ireland in the 1990s, MA Thesis, Dublin City University. p10

Cablevision rolled out CATV systems in Waterford and Galway.

In 1981, Marlin Communal Aerials Ltd. acquired Phoenix Relays Ltd and formed Dublin Cablesystems Ltd. (DCS). The Canadian company Rogers Cable owned Cablevision and Dublin Cablesystems through their purchase of Perimer Cablevision in 1980. In 1984, RTÉ proposed to buy 75% of DCS in an aim to modernise cable systems that had an "urgent need for modernisation and development which was impossible under present conditions".Flanagan, P. (1994) Cable TV in Ireland in the 1990s, MA Thesis, Dublin City University. p11

There was little regulation of cable systems during the early years; often it was there to redistribute British channels and improve RTÉ's reception. With this in mind, RTÉ was allowed buy a 75% share in DCS and 1986 formed Cablelink. Cablelink had approximately 200,000 subscribers. By 1990, almost 300,000 homes had cable subscriptions and the Government began to regulate the MMDS system.Kearny, R. (1988) Across The Frontiers: Ireland in the 1990s: Cultural, Political and Economical, 1st ed., Dublin: p220

MMDS (1990-2016) MMDS was used to distribute multichannel television to non-cabled areas between 1989 and 2016. While "cable" television generally refers to services provided by cables, legally MMDS television distribution systems, which were widespread in some regions of rural Ireland, were classified as a form of "cable" television. The introduction of MMDS began in 1989, with the network of 29 cells forming a "national grid" being regulated for, if not intact, by 1998.

Analogue MMDS specifications were legally set in 1998 by the then Office of the Director of Telecommunications Regulation in the document "Technical conditions for the operation of analogue programme services distribution systems in the frequency band 2500-2686 MHz"

Virgin Media Digital MMDS used a DVB-C variant on ex NTL MMDS and a variant of DVB-T on ex Chorus MMDS networks.

One of the first MMDS operators provided 11 channels, but RTÉ One or Network 2 did not appear on the service, rather, their CEO insisted on the RTÉ News that customers could already receive those transmission terrestrially and his product was about providing more choice.Lally, M. (1990). Report into MMDS TV providers. IN: Six O'clock News. RTÉ1. 12 April 1990. view here https://www.youtube.com/watch?v=cCFBSjuiyUY.(Lally: Six One News)