The Machynlleth transmitting station is a broadcasting and telecommunications facility located on a hill about west of the town of Machynlleth, in Powys, Wales. It was originally built by the BBC, entering service in June 1965 acting as a relay transmitter for the now-defunct 405-line VHF television system.
Specifications The site originally consisted of a pair of wooden telegraph poles (one for the transmitting aerials, one for the receiving aerials) erected on land that is itself about above sea level. The television broadcasts primarily covered the town of Machynlleth and the villages of the upper Dyfi river valley.
625-line colour TV came to the site in the late 1970s. A new self-supporting lattice mast was built to carry the UHF aerials but the original VHF TV and VHF radio services continued to use the site's original wooden poles.
The three original VHF radio transmitters were upgraded to stereo in late Spring 1983.
The 405-line VHF television service closed across the UK in 1985, but Machynlleth's 405 line services closed a year early - in January 1984.
Machynlleth currently broadcasts digital television and analogue FM radio.
Services listed by frequency
Analogue television
28 June 1965 - Late 1970s The transmitter was classed as a relay of Blaenplwyf about to the southwest, receiving its signal by direct off-air pickup.
FrequencyVHFkWService5H0.05BBC1 Wales
Late 1970s - 1 November 1982 Colour TV eventually arrived, with the site continuing to act as an off-air relay of Blaenplwyf for the 625-line services.
FrequencyVHFUHFkWService5H—0.05BBC1 Wales—570.02BBC1 Wales—600.02HTV Wales—630.02BBC2 Wales
1 November 1982 - January 1984 Channel 4 launched across the UK on 1 November 1982. Being in Wales, Machynlleth broadcast the S4C variant.
FrequencyVHFUHFkWService5H—0.05BBC1 Wales—530.02S4C—570.02BBC1 Wales—600.02HTV Wales—630.02BBC2 Wales
January 1984 - 10 February 2010 405-line television was discontinued after 19 years of service. For the next 25 years there were to be no changes to the television output at this site.
FrequencyUHFkWService530.02S4C570.02BBC1 Wales600.02HTV Wales630.02BBC2 Wales
Analogue and Digital Television
10 February 2010 - 10 March 2010 Digital switchover started at Blaenplwyf and therefore at Machynlleth and all its other relays. BBC 2 was closed down on channel 63 and BBC 1 was moved from channel 57 to channel 63 for its final month of service. Mux A started up on the newly vacated channel 57 at full post-DSO power of 4 W.
FrequencyUHFkWServiceSystem530.02S4CPAL System I570.004BBC ADVB-T600.02HTV WalesPAL System I630.02BBC1 WalesPAL System I
Digital Television
10 March 2010 - present All the remaining analogue TV transmitters were shut down and the three multiplexes of Freeview Lite took over their frequencies.
FrequencyUHFkWService530.004BBC B570.004BBC A600.004Digital 3&4
Analogue radio (FM VHF)
28 June 1965 - Early 1990s For its FM radio services, Machynlleth is an off-air relay of Blaenplwyf.
FrequencykWService89.4 MHz0.06BBC Light Programme91.6 MHz0.06BBC Third Programme93.8 MHz0.06BBC Welsh Home Service
Early 1990s - present Radio 1 gained its own frequency and National Radio 4 was added.
FrequencykWService89.4 MHz0.06Radio 291.6 MHz0.06Radio 393.8 MHz0.06Radio Cymru99.0 MHz0.06Radio 1103.6 MHz0.06Radio 4
See also List of masts List of radio stations in the United Kingdom List of tallest buildings and structures in Great Britain
References
External links MB21's page on BBC 405 TV to Wales and the West 405 Alive's list of transmitters" More details on 405-line BBC transmitters The Transmission Gallery: Photographs and Information