Llanddona transmitting station

The Llanddona transmitting station (/lænˈdɒnæ/; Welsh: [ɬanˈdɔna]); Welsh pronunciation) is a broadcasting and telecommunications facility, situated at Llanddona, near Beaumaris, on the isle of Anglesey, Wales (grid reference SH583810). It comprises a 106.7 metres (350 ft) guyed mast with antennas attached at various heights. It is owned and operated by Arqiva.

Llanddona
Llanddona transmitting station (Anglesey)
Mast height106.7 metres (350 ft)
Coordinates53.306944°N 4.128333°W / 53.306944; -4.128333
Grid referenceSH583810
Built1958
BBC regionBBC Wales
ITV regionITV Wales

History

The station was built by the BBC in 1958 to provide a 405-line Band I (VHF) TV service and (later) a VHF (FM) radio services for north west Wales, including the Lleyn peninsula, Anglesey and the north Wales coast. ITV's service was provided from the Arfon transmitting station, approximately 20 miles to the south on the mainland.

In 1967 the site became the area's main station for 625 line colour UHF TV, starting with just BBC Two in June of that year. By this time, it was policy to co-site all UHF TV services at the same site, and by 1973 Llanddona was broadcasting BBC One, BBC Two and ITV on UHF. S4C was added later in 1982 in time for its launch.

Though 405-line TV was discontinued in the UK in 1985, it seems that Llanddona shut down its VHF TV a year early.

In the late 1990s, digital TV transmitters were added, carrying all six national multiplexes.

In 2006, digital radio transmitters were added for the BBC's national multiplex and also Digital One.

On Wednesday 21 October 2009, the Llanddona group of transmitters underwent the first stage of the Digital Switchover and on Wednesday 18 November 2009, analogue television was finally turned off from Llanddona and its group of transmitters as it underwent the second stage of the Digital Switchover. Whilst the old analogue channels were in the UK UHF C/D aerial group, the new DVB channels are now spread over into the E group (presumably to avoid co-channel interference with Winter Hill transmitter), meaning that some customers may need to replace their aerial to get optimum reception.

Freeview HD started transmitting using the BBC B multiplex on channel 53 in July 2010.[1]

Llanddona was the site of the first TV, VHF radio, digital TV and digital radio broadcasts for the area.

Coverage area

The coverage area consists of the majority of Anglesey, and a wide range of other parts of the North West Wales coast. As with the service areas of other transmitters in North Wales, such as the Moel-y-Parc transmitting station, signal overspill from transmitters in North West England and Greater Manchester means that strong radio and television signals from that region (BBC North West and ITV Granada) can be received in North Wales, and strong Welsh signals can be received in North West England also. In the days of analogue TV, some people who received signals from the Llanddona transmitter, but who had no interest in S4C (a Welsh speaking channel) were known to erect a second aerial and receive Channel 4 from Winter Hill instead.

The transmitter signals were also received across the Irish sea in many parts of the east and south east coast of the Republic of Ireland, mainly in counties Dublin and Wicklow. From 1958 onward, many households in these counties would point their outdoor aerials towards the Irish sea and could receive transmission from this transmitter. When cable television launched in the early 1970s, the Welsh BBC and ITV stations were provided on the cable platform as these channels were mainly received in the Dublin and Wicklow counties.

Services listed by frequency

January 1958 - 3 June 1967

it is unclear when transmissions began. "The Big Tower" claim[2] that 405-line television from Llanddona started in January 1958, and the entrance plaque to the transmitter building[3] certainly agrees that the mast and its building were built in 1958. Oddly, BBC research report 1963-50[4] does not mention a start date though it does point out that co-channel interference (presumably from Divis in Northern Ireland, about 180 km to the northwest across the Irish Sea) was "severe". This caused the transmitter's useful service area to be smaller than planned, and forced the building of the Holyhead relay.

"405 Alive" counter-claim[5] a very precise date of 15 May 1962 for the start of 405-line television.

Frequency VHF kW Service
45.00 MHz 1V 6 BBC1 Wales

3 June 1967 - 6 September 1973

The first UHF transmitter at the site entered service.[6]

Frequency VHF UHF kW Service
45.00 MHz 1V — 6 BBC1 Wales
807.25 MHz — 63 100 BBC2 Wales

6 September 1973 - 1 November 1982

ITV's transmissions certainly started on 6 September,[7] but is likely that the BBC 1 Wales UHF service had already commenced before then.

Frequency VHF UHF kW Service
45.00 MHz 1V — 6 BBC1 Wales
759.25 MHz — 57 100 BBC1 Wales
783.25 MHz — 60 100 HTV Wales
807.25 MHz — 63 100 BBC2 Wales

1 November 1982 - January 1984

Channel 4 launched across the UK. Being in Wales, Llanddona transmitted the S4C variant.

Frequency VHF UHF kW Service
45.00 MHz 1V — 6 BBC1 Wales
727.25 MHz — 53 100 S4C
759.25 MHz — 57 100 BBC1 Wales
783.25 MHz — 60 100 HTV Wales
807.25 MHz — 63 100 BBC2 Wales

January 1984 - 15 November 1998

The 405-line VHF TV transmission was discontinued after 22 years of service.

Frequency UHF kW Service
727.25 MHz 53 100 S4C
759.25 MHz 57 100 BBC One Wales
783.25 MHz 60 100 HTV Wales
807.25 MHz 63 100 BBC Two Wales

15 November 1998 - 21 October 2009
Frequency UHF kW Service System
674.000 MHz 46 1 Arqiva (Mux D) DVB-T
706.000 MHz 50 1 BBC (Mux 1) DVB-T
727.25 MHz 53 100 S4C PAL System I
738.166 MHz 54+ 1 Digital 3&4 (Mux 2) DVB-T
759.25 MHz 57 100 BBC One Wales PAL System I
770.166 MHz 58+ 1 SDN (Mux A) DVB-T
783.25 MHz 60 100 ITV1 Wales (HTV Wales until 2002) PAL System I
794.166 MHz 61+ 1 BBC (Mux B) DVB-T
807.25 MHz 63 100 BBC Two Wales PAL System I
818.166 MHz 64+ 1 Arqiva (Mux C) DVB-T

21 October 2009 - 18 November 2009

The BBC Two analogue signal was switched off after 32 years of service, and BBC One analogue was moved to channel 63. Multiplex 1 on channel 50 was also discontinued. The new "BBC A" multiplex took over on channel 57 which had just been vacated by BBC One analogue with its full post-DSO ERP of 20 kW. BBC A is an expanded version of the BBC's multiplexes 1 and B (with several channels, such as BBC Four and radio stations temporarily available on both BBC multiplexes).

Frequency UHF kW Service System
674.000 MHz 46 1 Arqiva (Mux D) DVB-T
727.25 MHz 53 100 S4C PAL System I
738.166 MHz 54+ 1 Digital 3&4 (Mux 2) DVB-T
762.000 MHz 57 20 BBC A DVB-T
770.166 MHz 58+ 1 SDN (Mux A) DVB-T
783.25 MHz 60 100 ITV1 Wales PAL System I
794.166 MHz 61+ 1 BBC (Mux B) DVB-T
807.25 MHz 63 100 BBC One Wales PAL System I
818.166 MHz 64+ 1 Arqiva (Mux C) DVB-T

18 November 2009 - 14 November 2012

All the remaining analogue TV was discontinued, and the new post-DSO multiplexes took over their frequencies plus a couple of new ones. Frequencies above 800 MHz were not re-used as these will be reassigned to 4G mobile phone services.

Frequency UHF kW Operator
650.000 MHz 43 10 SDN
674.000 MHz 46 10 Arqiva A
706.000 MHz 50 10 Arqiva B
730.000 MHz 53 20 BBC B
762.000 MHz 57 20 BBC A
786.000 MHz 60 20 Digital 3&4

14 November 2012 - present

As a side-effect of frequency-changes elsewhere in the region to do with clearance of the 800 MHz band for 4G mobile phone use,[8] Llanddona's "Arqiva B" multiplex was moved from channel 50 to channel 40, and "D3&4" on channel 60 gained a negative frequency offset.[9]

Frequency UHF kW Operator
626.000 MHz 40 10 Arqiva B
650.000 MHz 43 10 SDN
674.000 MHz 46 10 Arqiva A
730.000 MHz 53 20 BBC B
762.000 MHz 57 20 BBC A
785.833 MHz 60- 20 Digital 3&4
  • Aerial group: W
  • Polarisation: horizontal

1960 - Early 1990s

VHF FM radio was in service by October 1960 as evidenced by a BBC research report.[10]

Frequency kW Service
89.6 MHz 12 BBC Light Programme
91.8 MHz 12 BBC Third Programme
94.0 MHz 12 BBC Welsh Home Service

Early 1990s - present

Radio 1 got its own frequency and National Radio 4 was added to the set. Additionally, the frequencies for the original three services were increased by 200 kHz each.

Frequency kW Service
89.8 MHz 21 BBC Radio 2
92.0 MHz 21 BBC Radio 3
94.2 MHz 21 BBC Radio Cymru
94.8 MHz 10 BBC Radio Wales
99.4 MHz 21 BBC Radio 1
103.6 MHz 21 BBC Radio 4

Digital radio
Frequency Block kW[11] Operator
222.064 MHz 11D 1 Digital One
225.648 MHz 12B 5 BBC National DAB

See also

References
  1. "Freeview". Freeview. Retrieved 28 May 2013.
  2. "TheBigTower Llanddona Transmitter". Thebigtower.com. Retrieved 28 May 2013.
  3. "Entrance Plaque at Llanddona Transmitting Station:: OS grid SH5881 :: Geograph Britain and Ireland - photograph every grid square!". Geograph.org.uk. Retrieved 28 May 2013.
  4. http://downloads.bbc.co.uk/rd/pubs/reports/1963-50.pdf
  5. "405 Alive - Information - A List of VHF 405-Line Transmitters". Bvws.org.uk. Retrieved 28 May 2013.
  6. http://downloads.bbc.co.uk/rd/pubs/reports/1967-39.pdf
  7. "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 28 May 2013.
  8. Summers, Nick (15 February 2012). "EU States Must Allow 4G on Analogue TV Spectrum". Thenextweb.com. Retrieved 28 May 2013.
  9. "4G clearance retunes". a516digital. Retrieved 28 May 2013.
  10. http://downloads.bbc.co.uk/rd/pubs/reports/1960-24.pdf
  11. Radio Listeners Guide 2010
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