Yorkshire TV timeline: Highs and lows of 40 years on air

1968 Yorkshire TV goes on air – the first time Yorkshire has had its own production facility. Programmes were previously broadcast to the region from Granada and ABC-TV Manchester.

1969 The station briefly goes off the air when its transmitter mast at Emley Moor collapses under a heavy build-up of ice.

1972 Emmerdale Farm is launched, initially as an afternoon serial. It would be many years before it would be screened simultaneously at peak time across the network.

1974 YTV's most famous documentary is screened. Too Long a Winter, directed by Barry Cockcroft, introduced Yorkshire Daleswoman Hannah Hauxwell and her austere and harsh lifestyle running her remote farm.

1975 YTV transmits the award-winning documentary Johnny Go Home, a startling expose of teenage male prostitution and homelessness in London.

1977 Yorkshire launches Britain's first breakfast TV series, as a nine-week experiment, The 8.30am programme was called Good Morning Calendar.

1978 YTV celebrates its tenth anniversary with the launch of a large-scale quiz show called 3-2-1. Hosted by the late Ted Rogers, it would run for ten years.

1979 A technicians' strike takes the whole of ITV off the air for weeks. During the blackout, West Yorkshire Police interrupts the test card with appeals for information about the Yorkshire Ripper killings.

1982 Channel 4 launches with its first programme broadcast from YTV in Leeds - the long-running Countdown.

1983 YTV launches its award-winning documentary series, First Tuesday. Its films included a famous expose of conditions at the Windscale nuclear plant in Cumbria (now Sellafield).

1986 YTV launches Britain's first all-night TV service - a joint venture with the satellite station Music Box

1989 The first real commercial rival to ITV launches - Rupert Murdoch's Sky Television.

1990 YTV produces its hugely successful drama The Darling Buds of May, beginning a long association with the actor David Jason.

1991 ITV's new franchises are awarded. In London, Thames TV was forced off the air but YTV retained its licence - with a high bid that proved unsustainable.

1992 The 1960s drama series Heartbeat launches. Initially feared to be a flop, it is still on air today, although ITV has announced production is now to be suspended.

1993 A change in legislation paves the way for consolidation within ITV. YTV, struggling under the weight of its new franchise payments, is taken over by its Lancashire neighbour Granada.

1997 Channel Five launches, the last of the terrestrial stations.

1998 OnDigital (later renamed ITV Digital) is launched as a rival to BSkyB. Its ultimate failure led directly to the creation of today's BBC-backed Freeview service.

2001 BBC1 overtakes ITV as nation's most popular channel. Since its launch in 1955, ITV had consistently outranked its rival.

2003 The Communications Act sets up a new regulator, Ofcom, replacing the Independent Television Commission. Protection for less profitable programming such as children's and religion, is withdrawn.

2003 The merged ITV Carlton and Granada groups consolidate further into a single company. Only Scotland, Northern Ireland and the tiny Channel Islands remain outside the new company.

2004 ITV begins the roll-out of digital channels ITV2, ITV3 and ITV4. The company buys the Friends Reunited social networking website for 120m and launches its ITV Local web-based business. Today it announced it was closing that and selling Friends Reunited.

2006 A takeover bid from former BBC director general Greg Dyke, valuing ITV at 130 pence per share, is rejected.

2007 Michael Grade joins ITV as executive chairman. A scandal erupts surrounding the use of premium rate phone lines on programmes such as Ant & Dec's Saturday Night Takeaway and The British Comedy Awards - both of which ran competitions or votes viewers had no chance of influencing.

2008 ITV announces heavy cuts in its regional news network. In Yorkshire, separate editions of Calendar for East and South Yorkshire are scrapped.

2009 ITV proposes a merger with Channel 4 and Channel Five to create a single advertising-funded operation to rival the BBC and BSkyB.

2009 The much-rumoured closure of YTV's studios in Leeds is confirmed as ITV publishes its annual results.

R.I.P. Yorkshire TV: Full coverage