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This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. (May 2008) |
| Crystal Palace | |
 |
|
| Height of Mast | 219 metres (719 ft)[1] |
|---|---|
| Built | 1956 |
| BBC Region | BBC London |
| ITV Region | ITV London |
The Crystal Palace transmitting station is a broadcasting and telecommunications site in the Crystal Palace area of the London Borough of Bromley, England (grid reference TQ339712).
Its tower is the second-tallest structure in London. The station is best known as the main television transmitter for the London area.
Contents |
History and development
The station was constructed in the mid-1950s among the ruins of the Crystal Palace. The Aquarium on which it stands was accidentally destroyed in 1941 during the demolition of the Palace's north water tower[2][3]. (John Logie Baird's earlier transmitter and TV studios were a separate development at the other end of the Palace and perished with it in 1936.[4][5])
Its new 219-metre (719 ft)[1] tower was the tallest structure in London until the construction of One Canada Square at Canary Wharf in 1991. Despite its size, it has been largely overlooked as a London landmark due to its location and simplicity.[citation needed] It has been nicknamed London's Eiffel Tower.
When first constructed it only transmitted BBC Television on the old VHF 405-line system. The Croydon transmitter was then built to broadcast ITV. When UHF transmissions started in 1964 first the new BBC2 and later both ITV and BBC1 were then transmitted from Crystal Palace. However, even now Crystal Palace does not transmit analogue Channel 5, this (alone) comes from Croydon about two miles away (although Croydon does have reserve transmitters for ITV and Channel 4, which are only used in the event of a fault or maintenance at Crystal Palace). A couple of years ago[clarify] the BBC decided that a complete reserve was also a good idea and now all four services are available from Croydon if required. When UK Digital Switch Over is completed in the London area in 2012 all services will come from Crystal Palace again, but because of the site's importance Croydon will be able to be used to duplicate the PBS multiplexes in case of emergency. 405-line VHF television was discontinued in 1985, and now the only television broadcasts from Crystal Palace are on UHF.
The station carries the London regions of BBC One, BBC Two, ITV1 and Channel 4 in analogue, each with an effective radiated power of 1 MW, as well as all six digital terrestrial television multiplexes. These have an ERP of 20 kW, with considerable beam tilt to the south and east. Although DTT requires far less power to achieve the same coverage as analogue TV, this 17 dB difference is too large to ensure comparable coverage. The station therefore has a range of about 30 miles (50 km) for DTT, compared with about 60 miles (90 km) for analogue.
The tower is also used for FM radio transmission of several local radio stations BBC London 94.9, XFM, Choice FM and Virgin Radio, as well as a low powered relay of the 4 BBC national FM services and Classic FM. It also has mediumwave transmitters on 558 kHz (Spectrum Radio), 720 kHz (BBC Radio 4) and 1035 kHz (Kismat Radio). Since the tower is grounded, a wire aerial spun close to it is used for the MW services.
Since 1995, the tower has also been in use as one of five London transmitters for the BBC DAB multiplex. This was joined in 1999 by the Digital One DAB service, and a further local DAB multiplex has also since started transmitting.
In May 2006, Crystal Palace began broadcasting the first terrestrial HDTV signals in the UK. This was to enable a trial group of 450 London homes to test HD broadcasts by the BBC, ITV, Channel 4 and Five, in order to assess the viability and potential problems of future nationwide HD broadcasting.
Future developments
The UK Government's plans for digital switchover are based on the use of almost all of the UK's current analogue TV transmitter sites. As such, Crystal Palace is expected to remain a key part of the network when the London area is switched over in 2012. In July 2007 it was confirmed by Ofcom that Crystal Palace would be remaining an A group transmitter after DSO (Digital Switchover).
Channels listed by frequency
Analogue Radio (AM Medium wave)
- 558 kHz - Spectrum
- 720 kHz - BBC Radio 4
- 1035 kHz - Kismat Radio
Analogue Radio (FM VHF)
- 88.8 MHz - BBC Radio 2
- 91.0 MHz - BBC Radio 3
- 93.2 MHz - BBC Radio 4
- 94.9 MHz - BBC London
- 96.9 MHz - Choice FM
- 98.5 MHz - BBC Radio 1
- 100.6 MHz - Classic FM
- 104.9 MHz - XFM
- 105.8 MHz - Virgin Radio
Digital Radio (DAB)
- Block 11D: 222.064 MHz - Digital One
- Block 12A: 223.936 MHz - Switch London
- Block 12B: 225.648 MHz - BBC
Analogue Television
- UHF 23 (487.25 MHz) - ITV1 London (Carlton Television/London Weekend Television)
- UHF 26 (511.25 MHz) - BBC One London
- UHF 30 (543.25 MHz) - Channel 4
- UHF 33 (567.25 MHz) - BBC Two
Digital Television
- UHF 22 (482 MHz) - Multiplex 2 - Digital 3&4
- UHF 25 (506 MHz) - Multiplex 1 - BBC
- UHF 28 (530 MHz) - Multiplex B - BBC
- UHF 29 (538 MHz) - Multiplex D - National Grid Wireless
- UHF 32 (562 MHz) - Multiplex A - S4C Digital Networks
- UHF 34 (578 MHz) - Multiplex C - National Grid Wireless
See also
- Tall buildings in London
- National Grid Wireless (which owns the tower)
- Radio masts and towers
- List of Towers
- List of tallest buildings and structures in Great Britain
- List of radio stations in the United Kingdom
External links
- The Transmission Gallery: Crystal Palace Transmitter photographs and information
- Pictures and info on Crystal Palace, including co-receivable transmitters
- http://skyscraperpage.com/cities/?buildingID=3886
- Crystal Palace Transmitter in the Structurae database
- Ofcom local transmitter advice
References
- ^ a b "NGW planning application". Bromley Council planning portal (2008-04-23). Retrieved on 2008-09-13.
- ^ "War's Worst Raid" (1941-04-28). TIME. Retrieved on 2008-05-29.
- ^ Pescod, David FRS (2005-02-10). "Correspondence" (PDF). The Linnean 21 (2): 36. London: Linnean Society of London. Retrieved on 2008-05-29.
- ^ Glen, Richard E (2003-04-05). "Baird's independent television". Transdiffusion Broadcasting System. Retrieved on 2008-05-29.
- ^ Herbert, Ray (July 1998). "Crystal Palace Television Studios". Soundscapes 1 (4). Groningen, The Netherlands: University of Groningen. ISSN 1567-7745. Retrieved on 2008-05-29.
