test card (not to be confused with the SMPTE colour bars). On 18 July 1986, with the First Night of the Proms on BBC2, the transmitter became the first in the world to transmit stereophonic sound using the NICAM digital sound system. Television When built it transmitted BBC Television on the VHF 405-line system; the Croydon transmitter two miles away had been built some months earlier to broadcast ITV. When UHF transmissions started in 1964, first the new BBC2 and later both BBC 1 and ITV (Rediffusion weekdays and ATV London at weekends) were transmitted from Crystal Palace. Thames Television began in 1968 along with London Weekend which became London Weekend Television (LWT) in 1978. 405-line VHF television was discontinued at the start of 1985, and from then onwards all television broadcasts from Crystal Palace were only on UHF. Crystal Palace did not transmit analogue Channel 5: this (alone) came from Croydon. Croydon had reserve transmitters for ITV and Channel 4, used in the event of a fault or maintenance at Crystal Palace. The BBC decided that a complete reserve was also a good idea and all four services became available from Croydon if required. The station carried the London regions of BBC ONE, BBC TWO, ITV1 and Channel 4 in analogue, each with an effective radiated power of 1 MW, before the digital switchover took place during April 2012, as well as all six digital terrestrial television multiplexes. These had an ERP of 20 kW before switchover and 200 kW after, with considerable beam 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. 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 for DTT, compared with about for analogue. Radio It is also used for FM radio transmission of local radio stations BBC Radio London, Radio X, Capital Xtra and Absolute Radio, and a low-powered relay of the four BBC national FM services - Radio 1, Radio 2, Radio 3 and Radio 4, and Classic FM. It also has medium wave transmitters on 558 kHz (Panjab Radio), 720 kHz (BBC Radio 4) and 1035 kHz (Kismat Radio). Since