Llandrindod Wells transmitting station

Llandrindod Wells
Llandrindod Wells transmitting station (Powys)
Mast height 65 metres (213 ft)
Coordinates 52°15′38″N 3°26′22″W / 52.260429°N 3.43948°W / 52.260429; -3.43948Coordinates: 52°15′38″N 3°26′22″W / 52.260429°N 3.43948°W / 52.260429; -3.43948
Grid reference SO018634
Built 1961
Relay of Carmel
BBC region BBC Wales
ITV region ITV Wales

The Llandrindod Wells transmitting station is a broadcasting and telecommunications facility located on high ground about midway between Llandrindod Wells and Rhayader, in Powys, Wales. It was originally built by the BBC, entering service in 1961 transmitting the now-defunct 405-line VHF television system and the original three FM Radio services.[1][2]

Currently, the transmitter provides DVB-T digital television to the area, along with FM radio and a single multiplex of DAB digital radio.

Specifications and history

Originally, the site has a guyed 65 m lattice mast erected on land that is itself about 440 m above sea level. Unusually for the era, when 405-line Independent Television came to the area in 1969, the ITV transmissions were hosted on the same mast as the BBC ones.

UHF television was added to the site in late 1975,[3] launching with just the three programme services that were active at the time. S4C was added in 1982 when it launched.

405-line television from this site was shut down in January 1985.[4]

In 1991, the site was re-engineered. A self-standing 75 m lattice mast was erected on the site, the services were transferred from the old mast on 13 November 1991. The television broadcasts primarily cover the towns of Llandrindod Wells (to the east), Builth Wells (to the southeast) and Rhayader (to the northwest).

Services listed by frequency

Analogue television

4 December 1961 - 1964

BBC 405-line television started up with the site acting as an off-air relay transmitter of Wenvoe about 90 km to the south, near Cardiff. About 42 km south there is the 700 m ridge to the east of Pen y Fan which obstructs the line-of-sight, but the off-air signal was good enough, as evidenced by the BBC's 1963 report on long-distance rebroadcast links[5] (see map on page 8).

Frequency VHF kW Service
45.00 MHz 1 1.5 BBC TV

1964 - 4 July 1969

BBC Wales launched from Wenvoe on 9 February 1964 on channel 13, and the off-air repeaters of Wenvoe (within Wales) were reconfigured to use this signal.

Frequency VHF kW Service
45.00 MHz 1 1.5 BBC Wales

4 July 1969 - Late 1975

When ITV 405-line television commenced, the site additionally became an indirect off-air relay of Preseli about 90 km to the west. Available documentation does not state how the signal from Preseli was routed to Llandrindod Wells. There is a 30 km long stretch of high ground (the southern Cambrian hills) obstructing the direct signal from Preseli starting about 10 km to the west. However, the 100 W off-air relay at Llandovery is line-of-sight about 30 km away on a bearing of 218°.

Llandovery relay had been built a year earlier in 1968, and as can be deduced from the geometry of MB21's photos,[6] it was indeed chosen for the signal source. Eight yagi aerials (four in use, four as reserves) were needed to pick up a reliable signal off-air.

Frequency VHF kW Service
45.00 MHz 1 1.5 BBC1 Wales
194.75 MHz 9 3 HTV Wales

Late 1975 - 1 November 1982

When 625-line colour television was added, the site additionally became a relay of Carmel about 65 km to the southwest. This despite the fact that line-of-sight is obstructed about 24 km to the southwest by the slopes of Esgair Dafydd just north of the Sugar Loaf.

Frequency VHF UHF kW Service
45.00 MHz 1 — 1.5 BBC1 Wales
194.75 MHz 9 — 3 HTV Wales
615.25 MHz — 39 2.25 BBC1 Wales
663.25 MHz — 45 2.25 BBC2 Wales
695.25 MHz — 49 2.25 HTV Wales

1 November 1982 - 3 January 1985

Channel 4 was added to the set radiated from the site when it launched in November 1982. Being in Wales, Llandrindod Wells radiated the S4C variant.

Frequency VHF UHF kW Service
45.00 MHz 1 — 1.5 BBC1 Wales
194.75 MHz 9 — 3 HTV Wales
615.25 MHz — 39 2.25 BBC1 Wales
639.25 MHz — 42 2.25 S4C
663.25 MHz — 45 2.25 BBC2 Wales
695.25 MHz — 49 2.25 HTV Wales

3 January 1985 - 26 August 2009

405-line television was shut down across the UK and Llandrindod Wells' Band I and Band III transmitters ended their service after 24 years and 16 years respectively. From then until the start of the digital switchover 24 years later, only UHF television would be available from the site.

Frequency UHF kW Service
615.25 MHz 39 2.25 BBC One Wales
639.25 MHz 42 2.25 S4C
663.25 MHz 45 2.25 BBC Two Wales
695.25 MHz 49 2.25 ITV1 Wales (HTV Wales until 2002)

Analogue and digital television

26 August 2009 - 23 September 2009

The UK's digital switchover commenced, mirroring the changes taking place at the parent transmitter at Carmel. Analogue BBC Two Wales closed on channel 45 and ITV1 Wales took over on that frequency for what would be its final 3 weeks of service, vacating channel 49 as it did so. The new digital BBC A multiplex started up at full power in 64-QAM mode on channel 49.

Frequency UHF kW Service System
615.25 MHz 39 2.25 BBC One Wales PAL System I
639.25 MHz 42 2.25 S4C PAL System I
663.25 MHz 45 2.25 ITV1 Wales PAL System I
698.000 MHz 49 0.4 BBC A DVB-T

Digital television

23 September 2009 - present

All the analogue television services closed and the new digital multiplexes took over their frequencies.

Frequency UHF kW Operator
642.000 MHz 42 0.4 Digital 3&4
666.000 MHz 45 0.4 BBC B
698.000 MHz 49 0.4 BBC A

Analogue radio (FM VHF)

4 December 1961 - Circa 1990

From the outset, Llandrindod Wells radiated the BBC's three FM radio services, acting as an off-air relay of Wenvoe.

Frequency kW Service
89.1 MHz 1 BBC Light Programme
91.3 MHz 1 BBC Third Programme
93.5 MHz 1 BBC Welsh Home Service

Present

Radio 2, Radio 3 and Radio Cymru still use the original frequencies that have been used since 1961. Radio 1 and Radio 4 commenced transmission from this site on 13 November 1991. Radio 4, along with Radio Cymru, have replaced the Welsh Home Service (later known as Radio Wales).

Frequency kW Service
89.1 MHz 1.4 BBC Radio 2
91.3 MHz 1.4 BBC Radio 3
93.5 MHz 1.4 BBC Radio Cymru
98.7 MHz 1.4 BBC Radio 1
103.8 MHz 1.4 BBC Radio 4

Digital radio (DAB)

Present

Frequency Block kW Operator
225.648 MHz 12B 5 BBC National DAB

See also

References

  1. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1964-26.pdf
  2. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1956-24.pdf
  3. ↑ "Welcome to the Gallery Upgrader". Txlib.mb21.co.uk. Retrieved 2013-05-28.
  4. ↑ "Archived copy". Archived from the original on 2012-08-13. Retrieved 2013-11-15.
  5. ↑ http://downloads.bbc.co.uk/rd/pubs/reports/1963-10.pdf
  6. ↑ "mb21 - The Transmission Gallery". Tx.mb21.co.uk. 2012-02-07. Retrieved 2013-05-28.
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