 | |
  Crystal Palace transmitting station (Greater London) | |
| Tower height | 219 metres (719 ft)[1] |
|---|---|
| Coordinates | 51°25′27″N0°04′30″W / 51.4242°N 0.0750°W /51.4242; -0.0750 |
| Built | 28 March 1956 |
| BBC region | BBC London |
| ITV region | ITV London |
| Local TV service | London Live |
TheCrystal Palace transmitting station, officially known asArqiva Crystal Palace, is a broadcasting and telecommunications site in theCrystal Palace area of theLondon Borough of Bromley, England (grid referenceTQ339712).[2] It is located on the site of the former television station and transmitter operated byJohn Logie Baird from 1933.[3]
The station is theeighth-tallest structure in London, and is best known as the main television transmitter for theGreater London area and parts of the surroundingHome Counties. As such, it is the most important transmitter in the UK in terms of population covered. The transmitter is owned and operated byArqiva. Given the transmitter's location on top of a 109-metre (358 ft) hill, it is the highest structure above sea level in London.
The station was constructed in the mid-1950s among the ruins ofthe Crystal Palace. The Aquarium on whose site it stands was destroyed in 1941 during the demolition of the Palace's north water tower.[4][5] (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.)[6][7] Its new 219-metre (719 ft)[1] tower was the tallest structure in London until thetopping-out ofOne Canada Square atCanary Wharf in 1990.
The first transmission from Crystal Palace took place on 28 March 1956, when it succeededthe transmitter at Alexandra Palace where the BBC had started the world's first scheduled television service in November 1936. In November 1956 the first colour test transmissions began from Crystal Palace, relaying live pictures from the studios at Alexandra Palace after BBC TV had closed down for the night. In May 1958 the first experimental Band V 625-line transmissions started from Crystal Palace.
This tower was designed and built for BBC by British Insulated Callender's Construction Co. Ltd., with steelwork fabrication byPainter Brothers Ltd. of Hereford. The tower was required to transmit television programmes with good reception in 1957, and has a total height of 708 feet (216 m). The base of the tower is 120 feet (37 m) to a side, and it rises in twelve diminishing panels to a 14.5 feet (4.4 m) square platform at a height of 429 feet (131 m).[8] The tower was constructed using two masts asderricks, one 230 feet (70 m) and the other 125 feet (38 m) high, in conjunction with awinch. At the time, a16mm film of the construction by BICC was produced; "The Phoenix Tower - The Story of the Crystal Palace Television Tower"[9] was available on loan from the BICC Film Library and has been released on the DVD "The Pleasure Garden" from theBFI.[10][11]
The transmitter was the first in the UK to broadcast (experimentally) on625 lines (UHF) in 1962–1964, which it did on Channel 44, using a modified version of theSMPTE opticalmonochrometest card[12] (not to be confused with theSMPTE colour bars).
On 18 July 1986, with theFirst Night of the Proms on BBC2, the transmitter became the first in the world to transmit stereophonic sound using theNICAM digital sound system.
When built it transmitted BBC Television on theVHF405-line system; theCroydon transmitter two miles away had been built some months earlier to broadcastITV. WhenUHF transmissions started in 1964, first the new BBC2 and later (from 1969) both BBC 1 and ITV were transmitted from Crystal Palace. 405-line VHF television was discontinued at the start of 1985.[13]
The station carried the London regions ofBBC One,BBC Two,ITV1 and Channel 4 in analogue, each with aneffective radiated power of 1 MW, before digital switchover took place during April 2012, as well as all sixdigital terrestrial televisionmultiplexes. These had aneffective radiated power of 20 kW before switchover and 200 kW after, with considerablebeam tilt to the south and east. With digital switchover completed all services come from Crystal Palace again, but because of the site's importance Croydon will be able to duplicate the PSB multiplexes in case of emergency.DTT requires less power to achieve the same coverage as analogue TV, hence the transmission powers have been reduced by 7dB compared to analogue;[14] however, the coverage range of approximately 60 miles (97 km) was expected to be largely similar post-switchover.[citation needed]
It is also used forFM radio transmission of local radio stationsBBC Radio London,Radio X,Capital Xtra andGreatest Hits Radio London (which until March 2021 carriedAbsolute Radio), and a low-powered relay of the four BBC national FM services -Radio 1,Radio 2,Radio 3 andRadio 4, andClassic FM. It also hasmedium wave transmitters on 558kHz (Panjab Radio)) and 1035 kHz (Lyca Gold). Since the tower is grounded, a wire aerial span close to it is used for theMW services.
Since 1995 the tower has been one of five London transmitters for theBBCDABmultiplex. This was joined in 1999 by theDigital One DAB service, and a further local DAB multiplex has since started transmitting, on behalf of theKlarna shopping channel.
BBC Radio 4's mediumwave frequencies from this transmitter ended on 15 April 2024 following a retune loop informing listeners to retune.[15][16]
In May 2006 it began broadcasting the first terrestrialHDTV signals in the UK to a trial group of 450 London homes to test HD broadcasts by the BBC, ITV, Channel 4 and Channel 5, to assess the viability and potential problems of future nationwide HD broadcasting. On 2 December 2009 the site entered service as one of the firstDVB-T2 transmitters in the world, carrying a variant of the BBC's Multiplex B broadcasting high-definition TV services.
The Government's plans fordigital switchover were based on the use of almost all current analogue TV transmitter sites. Crystal Palace remained a key part of the network after analogue was switched off in the London area in April 2012. In July 2007 it was confirmed by Ofcom that Crystal Palace would remain an A group transmitter after DSO (digital switchover). This was partially reversed with the 700 MHz Clearance that resulted in the use of Channels 55 and 56 for digital television both outside the A Group.[citation needed]
The transmitter is only one of two (the other being theITV Granada transmitter atWinter Hill) that alone providesITV andBBC services for the whole of their region, although still supported by the usual network of relays. Between opening in 1974 and January 1982, themain transmitter atBluebell Hill broadcastITV London signals to much of north and centralKent. However, theIndependent Broadcasting Authority (IBA), the then regulator of commercial television, reorganised the ITV franchises which saw Bluebell Hill transferred to a new south and south-east dual-region of ITV (Television South – TVS), which took effect from 1 January 1982. Bluebell Hill now transmitsITV Meridian andBBC South East.[citation needed]
As one would expect for the largest transmitter in the country – by population coverage – Crystal Palace transmitter remained an A group, (which was its original analogue group) both during dual running (analogue and low-power pre-DSO digital) and full-power digital after DSO. However, in March 2018, during the transmitter's 700 MHz clearance, the temporary MUXES 7 and 8 were moved out of group to CH55 and CH56. Thus, reception of the latter two MUXES now requires a wideband or K group aerial. MUXES 7 and 8 were, however, due to be switched off sometime before 2023.
On 18 April 2012, a public lighting display was performed from the tower to mark the last day of analogue TV broadcasts from the transmitter.[17][18][19]
The three most powerful relays areReigate (covering a large area of southSurrey and northern areas ofWest Sussex), Guildford (for theGuildford area and parts of south west Surrey)[20] and Hemel Hempstead (parts ofHertfordshire).[21] There are also low-power relays situated acrossGreater London and also in parts ofKent,West Sussex,Surrey,Oxfordshire,Buckinghamshire and Hertfordshire.
| Frequency | kW | Service |
|---|---|---|
| 558 kHz | 1 | Panjab Radio |
| 1035 kHz | 2.5 | Lyca Gold (moved to west London) |
These frequencies were used byLots Road until Tuesday 25 September 2001.
| Frequency | kW | Service |
|---|---|---|
| 88.8 MHz | 4† | BBC Radio 2 |
| 91.0 MHz | 4† | BBC Radio 3 |
| 93.2 MHz | 4† | BBC Radio 4 |
| 94.9 MHz | 4 | BBC Radio London |
| 96.9 MHz | 0.03 | Capital Xtra |
| 98.5 MHz | 4† | BBC Radio 1 |
| 100.6 MHz | 2 (V)† | Classic FM |
| 104.9 MHz | 2.9 | Radio X |
| 105.8 MHz | 3.73 | Greatest Hits Radio London |
† Relay ofWrotham.
| Frequency | Block | kW | Operator |
|---|---|---|---|
| 213.360 MHz | 10C | 3 | MuxCo Surrey & South London |
| 216.928 MHz | 11A | 5.7 | Sound Digital |
| 222.064 MHz | 11D | 6.5 | Digital One |
| 223.936 MHz | 12A | 3 | Switch London |
| 225.648 MHz | 12B | 10 | BBC National DAB |
After switchover[edit]
| Before switchover[edit]
|
BBC2 analogue was shut down on UHF 33 on 4 April 2012, and ITV London was temporarily moved from UHF 23 into BBC2's frequency of UHF 33. The remaining analogue services shut down on 18 April 2012.
| Frequency | UHF | kW | Service |
|---|---|---|---|
| 487.25 MHz | 23 | 1000 | ITV London |
| 511.25 MHz | 26 | 1000 | BBC1 London |
| 543.25 MHz | 30 | 1000 | Channel 4 |
| 567.25 MHz | 33 | 1000 | BBC2 |
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