Dolgellau transmitting station
The Dolgellau transmitting station is a broadcasting and telecommunications facility located on a hill about 1 km north of the town of Dolgellau, in Gwynedd, Wales. It was originally built by the BBC,[1] entering service just before Christmas 1967 acting as a relay transmitter for the now-defunct 405-line VHF television system. SpecificationsThe site has a self-standing 22 m lattice tower erected on land that is itself about 100 m above sea level. The television broadcasts primarily cover the towns of Dolgellau, Llanelltyd and the villages of the upper Mawddach river valley. 625-line colour TV came to the site in the late 1970s. The 405-line VHF television service closed across the UK in 1985, but Dolgellau's 405 line services closed early - in January 1984. Dolgellau currently broadcasts digital television and analogue FM radio. Services listed by frequencyAnalogue television18 December 1967 - Late 1970sThe transmitter was classed as a relay of Blaenplwyf about 40 km to the south, but received its signal from an SHF link fed from an off-air pickup on the coast at Barmouth about 10 km away to the west on the Mawddach estuary.
November 21st 1977 - 1 November 1982Colour TV eventually arrived, with the site now additionally acting as an indirect relay of Preseli (about 100 km to the south) for the 625-line services, receiving its signal off-air from Llwyn Onn, which receives its signal off-air from Preseli itself.[2]
1 November 1982 - January 1984Channel 4 launched across the UK on 1 November 1982. Being in Wales, Dolgellau broadcast the S4C variant.
January 1984 - 19 August 2009405-line television was discontinued (after a mere 17 years). For the next 25 years there were to be no changes to the television output at this site.
Analogue and Digital Television19 August 2009 - 16 September 2009Digital switchover started at Preseli and therefore at Dolgellau and all its other relays. BBC 2 was closed down on channel 62 and ITV 1 was moved from channel 59 to channel 62 for its final three weeks of service. Mux A started up on the newly vacated channel 59 at full post-DSO power.
Digital Television16 September 2009 - 31 October 2012All the remaining analogue TV transmitters were shut down and the three multiplexes of Freeview Lite took over their frequencies.
31 October 2012 - presentAs part of the Europe-wide clearance of the 800 MHz band,[3] the BBC Mux B signal was moved from channel 62- to channel 50.
Analogue radio (FM VHF)18 December 1967 - Early 1990sFor its FM radio services, Dolgellau is an off-air relay of Blaenplwyf.
Early 1990s - presentRadio 1 gained its own frequency and National Radio 4 was added.
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