Droitwich Transmitting Station

Droitwich
Masts at the Droitwich transmitting station
Droitwich Transmitting Station is located in Worcestershire
Droitwich Transmitting Station
Droitwich Transmitting Station (Worcestershire)
LocationDroitwich, Worcestershire
Mast height213.36 metres (700 ft)
Coordinates52°17′48″N 2°06′19″W / 52.296666666667°N 2.1052777777778°W / 52.296666666667; -2.1052777777778
Grid referenceSO929663
Built1934

The Droitwich transmitting station is a large broadcasting facility for long-wave and medium-wave transmissions, established in 1934 in the civil parish of Dodderhill, just outside the village of Wychbold, near Droitwich in Worcestershire, England (grid reference SO929663). The site is the location of the British Broadcasting Corporation's most powerful long-wave transmitter, which together with the two Scottish long-wave transmitters at Burghead and Westerglen forms a network broadcasting on the same frequency. The masts can be seen to the east from the M5 motorway, between Droitwich and Bromsgrove, as well as to the west from the Herefordshire/Worcestershire border. At night, the two sets of aircraft warning lights are visible from a long distance. The station is owned and operated by Arqiva.

History

In February 1932, radio broadcasting strength tests took place at Wychbold and Whittington, Worcestershire.[1]

By March 1932, it was decided to put the 5XX LW transmitter at Droitwich, at 120kW, and to boost the Midland Regional to 70 kW there.[2] The Wychbold site was chosen in December 1932.[3] The site was bought in March 1933, three miles north east of Droitwich.[4]

The foundations were built by May 1933.

In November 1933 the expected power was increased to 150kW, as that was the maximum allowed under the Lucerne Plan, which took effect on 15 January 1934.[5]

Tests began on Monday 30 July 1934 at 12.05am until 3am, to 31 August, except on Sundays. The station was expected to partly open on Thursday 6 September 1934, on 1,500 metres LW. It would open at 3.45pm until 4.15pm, then from 10.40pm in the evening. The first morning broadcast of the National programme would be the following day from 10.15am until 11.55am.[6]

The two masts were 180 tons each, 700 ft apart. Power came from four 750 hp English Electric (in Rugby) 'L type' diesel engines, [7] [8] each connected to a 470kW three phase alternator, producing enough power to supply 5,000 homes; exhaust from the engines powered the building's central heating. The engines ran at 375 rpm, with an output voltage of 415V.[9][10]

First broadcasts

The first item was the 1923 The Merrymakers overture, by Eric Coates, played by the BBC Symphony Orchestra, conducted by Aylmer Buesst.[11]

The full opening was on Sunday 7 October 1934. It was hoped a member of the Royal family would open the building, but none were available.[12]

Technical specifications

The long-wave frequency used was 200 kilohertz (frequently referred to by the wavelength, 1,500 metres) until 1 February 1988[13] when it was changed to 198 kilohertz, and the power is currently 500 kilowatts. The carrier frequency is controlled by a rubidium atomic frequency standard in the transmitter building, enabling the transmission to be used as an off-air frequency standard. For long-wave, a T-aerial is used, which is suspended between two 213-metre-high (700 ft) guyed steel lattice radio masts, which stand 180 metres (590 ft) apart from each other. There are also two guyed mast radiators at the site. The northerly mast is actually the transmitting antenna whilst the southern mast is a passive reflector causing the rf signal to form a cardioid pattern tending in a NE direction so as not to interfere with the similar set up in Bristol. The smaller mast system transmits digital radio signals. The main large system is used for transmitting AM medium-wave radio programmes on 693 kilohertz and 1053 kilohertz and, until 2023, on 1215 kilohertz.

Transmissions

BBC Radio 4 Longwave is transmitted on 198 kHz. This signal also carries radio data encoded using phase modulation, giving a time-of-day signal, and radio teleswitch control signals for Economy 7 electric-heating systems.

BBC Radio 5 Live is broadcast on 693 kHz medium wave (MW), providing coverage for most of the English Midlands and Wales at a signal strength (150 kW) which is one of the strongest for that station, equal to Brookmans Park and second only to Moorside Edge.

During World War II coded messages, which were read during normal programmed broadcasts, were sent to the French Resistance using the transmitter.[14]

In 2011, as a result of budget cuts, the BBC announced that there would be no re-investment in long wave transmissions, which may mean an eventual end to BBC Radio 4 Longwave broadcasts.[15] The same year, The Guardian reported that the transmitter relies upon a pair of glass valves, of which there are fewer than 10 left in the world, and the BBC did not believe it was safe enough to manufacture more, because "slightly faulty" replacements could cause catastrophic failure.[16] In 2023, the BBC announced that it would close down longwave transmissions sometime in 2024 and would end separate programming for the longwave transmitter in March 2024.[17] In March 2024, they announced that Radio 4 would turn off its medium wave frequencies and end its separate schedule for LW by April 15th.

BBC Radio 4 shut down its long wave transmitters on, or shortly after, this date.[18][19][20] 30 June 2025 will see the cessation of the usage of Radio 4's long wave frequencies for the radio teleswitching service.

Reception

The Radio 4 LW signal from Droitwich covers most of England and Wales. There are supplementary long-wave transmitters in Scotland (Burghead and Westerglen, both 50 kW). The station can also be heard clearly in most of the Republic of Ireland, particularly along eastern and southern counties. Reception is also possible in Western Europe, including Italy and Sweden.

Services available

Frequency kW Service
198 kHz 500 BBC Radio 4
693 kHz 150 BBC Radio 5 Live
1053 kHz 500 (night) 125 (day) Talksport

Formerly:

Frequency kW Service Ceased
1215 kHz 200 Absolute Radio January 20, 2023[21]

See also

References

  1. ^ Birmingham Daily Gazette Friday 26 February 1932, page 5
  2. ^ Staffordshire Sentinel Saturday 5 March 1932, page 3
  3. ^ Birmingham Daily Gazette Thursday 15 December 1932, page 11
  4. ^ Birmingham Daily Post Saturday 25 March 1933, page 18
  5. ^ Birmingham Daily Gazette Tuesday 16 January 1934, page 5
  6. ^ Daily Express Tuesday 14 August 1934, page 15
  7. ^ Staffordshire Advertiser Saturday 16 May 1936, page 6
  8. ^ Film
  9. ^ Newcastle Evening Chronicle Saturday 8 September 1934, page 5
  10. ^ Tewkesbury Register Saturday 8 September 1934, page 6
  11. ^ Gloucestershire Echo Friday 7 September 1934, page 4
  12. ^ Birmingham Daily Gazette Friday 5 October 1934, page 11
  13. ^ "BBCEng.Info - Droitwich Calling". Retrieved 31 January 2012.
  14. ^ "Droitwich calling". BBC Hereford & Worcester. 4 December 2007. Retrieved 22 September 2023.
  15. ^ "BBC set to cut 2,000 jobs by 2017". BBC News. 6 October 2011. Retrieved 22 September 2023.
  16. ^ "Radio 4's long wave goodbye". The Guardian. 9 October 2011. Retrieved 22 September 2023.
  17. ^ "BBC Radio 4 begins information campaign to transition listeners from Long Wave". www.bbc.co.uk. Retrieved 14 January 2024.
  18. ^ "Replacing your Radio Teleswitch electricity meter | Ofgem". www.ofgem.gov.uk. Retrieved 6 May 2024.
  19. ^ "The closure of radio teleswitching (RTS) explained". Retrieved 6 May 2024.
  20. ^ Team, The Clean Feed (1 May 2024). "Timeline: 2024 Week 18". Clean Feed. Retrieved 6 May 2024.
  21. ^ "Absolute Radio to switch off all AM transmitters across the UK". 4 January 2023.