The Black Hill transmitting station is a facility for FM and TV broadcasting at Black Hill (grid referenceNS828647), on Duntilland Road, Salsburgh, North Lanarkshire, Scotland which is near the town of Airdrie. It has a guyed mast 306.6 metres (1,006 ft) tall, bringing the antennas to a height of 540 metres above sea level. It was built, by the ITA, in 1957 and is now owned and operated by Arqiva.
The present mast is the second to have been built at the site. The first, built in 1957 brought the Independent Television service to Central Scotland and opened for service on 31 August 1957. Unfortunately complex anomalies in the behaviour of the antenna caused its performance to be less than predicted, and the decision was taken in 1959 to replace the mast with a higher structure and a more conventional aerial on the outside of the mast rather than inside as had been the case with the first mast. The original 750 foot mast was then dismantled and later used at the Selkirk station in the Borders where it still stands.
The transmitter was originally a B group but with the advent of Digital two of the 6 muxes are now out of band and require an E group (or wideband) aerial if reception of these is required. In July 2007 it was confirmed by Ofcom that Black Hill would be returning to a B group transmitter after DSO (Digital Switchover). Black Hill has the fifth greatest population coverage with a figure of around 2.5 million.
Between 1961 and the end of the 405 line ITV service in 1985 the Black Hill aerial had the highest effective radiated power of any transmitter in the ITV network with 475 kW radiated towards Dundee.
In the Summer of 2008 work began on the construction of a second 306.6 metre mast close to the original. This mast carries the new full-power Digital TV (DTT) services since digital switchover became effective at Black Hill in June 2011. The original mast will now be shortened in height and will radiate FM and DAB services only.
In June 2011, Black Hill became the final transmitter in Scotland to switch off analogue television. BBC Two Scotland was turned off first on 8 June, and the remaining four closed on 22 June.