Dolgellau transmitting station

Dolgellau
Tower height 22 metres (72 ft)
Coordinates 52°44′58″N 3°53′12″W / 52.7495°N 3.8867°W / 52.7495; -3.8867Coordinates: 52°44′58″N 3°53′12″W / 52.7495°N 3.8867°W / 52.7495; -3.8867
Grid reference SH727185
Built 1967
BBC region BBC Wales (1967-1982)

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.

Specifications

The 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 frequency

Analogue television

18 December 1967 - Late 1970s

The 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.

Frequency VHF kW Service
66.75 MHz 5V 0.026 BBC1 Wales

Late 1970s - 1 November 1982

Colour 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]

Frequency VHF UHF kW Service
66.75 MHz 5V — 0.026 BBC1 Wales
743.25 MHz — 55 0.02 BBC1 Wales
775.25 MHz — 59 0.02 HTV Wales
799.25 MHz — 62 0.02 BBC2 Wales

1 November 1982 - January 1984

Channel 4 launched across the UK on 1 November 1982. Being in Wales, Dolgellau broadcast the S4C variant.

Frequency VHF UHF kW Service
66.75 MHz 5V — 0.026 BBC1 Wales
743.25 MHz — 55 0.02 BBC1 Wales
775.25 MHz — 59 0.02 HTV Wales
799.25 MHz — 62 0.02 BBC2 Wales
823.25 MHz — 65 0.02 S4C

January 1984 - 19 August 2009

405-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.

Frequency UHF kW Service
743.25 MHz 55 0.02 BBC1 Wales
775.25 MHz 59 0.02 HTV Wales
799.25 MHz 62 0.02 BBC2 Wales
823.25 MHz 65 0.02 S4C

Analogue and Digital Television

19 August 2009 - 16 September 2009

Digital 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.

Frequency UHF kW Service System
743.25 MHz 55 0.02 BBC1 Wales PAL System I
778.000 MHz 59 0.004 BBC Mux A DVB-T
799.25 MHz 62 0.02 HTV Wales PAL System I
823.25 MHz 65 0.02 S4C PAL System I

Digital Television

16 September 2009 - 31 October 2012

All the remaining analogue TV transmitters were shut down and the three multiplexes of Freeview Lite took over their frequencies.

Frequency UHF kW Service
746.000 MHz 55 0.004 Digital 3&4
778.000 MHz 59 0.004 BBC Mux A
801.833 MHz 62- 0.004 BBC Mux B

31 October 2012 - present

As 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.

Frequency UHF kW Service
706.000 MHz 50 0.004 BBC Mux B
746.000 MHz 55 0.004 Digital 3&4
778.000 MHz 59 0.004 BBC Mux A

Analogue radio (FM VHF)

18 December 1967 - Early 1990s

For its FM radio services, Dolgellau is an off-air relay of Blaenplwyf.

Frequency kW Service
90.1 MHz 0.016 Radio 2
92.3 MHz 0.016 Radio 3
94.5 MHz 0.016 Radio 4 Wales

Early 1990s - present

Radio 1 gained its own frequency and National Radio 4 was added.

Frequency kW Service
90.1 MHz 0.02 Radio 2
92.3 MHz 0.02 Radio 3
94.5 MHz 0.02 Radio Cymru
99.7 MHz 0.02 Radio 1
103.6 MHz 0.02 Radio 4

See also

References

  1. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1968-49.pdf
  2. ↑ http://www.digitaluk.co.uk/__data/assets/pdf_file/0005/34925/Installer_Newsletter_Preseli__1_month_out_FINAL_24July_09.pdf
  3. ↑ http://thenextweb.com/eu/2012/02/15/eu-states-must-allow-4g-internet-use-on-analogue-tv-spectrum-by-january-2013/

External links

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