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The Carmarthen transmitting station (Welsh: Gorsaf drosglwyddo Caerfyrddin) was originally built by the BBC in 1964/65 as a relay for VHF radio and television. The site was built on a 135 m ridge to the north of Carmarthen itself, and entered service on 15 March 1965. The transmission station is now owned and operated by Arqiva.
UHF 625-line colour television was never radiated from this site: the main transmitter at Carmel (20 km to the east) provided that service to the town from 1973 when it opened.
The 405-line VHF television service closed across the UK in 1985, but according to the BBC's transmitter list and the BBC's internal "Eng. Inf." magazine, Carmarthen was due to close early - in the first quarter of 1982. From that point onwards the site just relayed FM radio until 6 June 2011 when a single multiplex of DAB radio was added.
Channels listed by frequency
Analogue television
15 March 1965 - First Quarter 1982
The site provided BBC 405-line VHF television to the towns of Carmarthen and Abergwili which, being sited in a river estuary, could not reliably receive a signal from Wenvoe, 85 km to the east.
The three original radio services were still on their original frequencies as late as January 1973, but ERPs had been slightly increased to 10 W per channel by then. By May 1978 all three transmission frequencies had been moved by 400 kHz and all three were transmitting in stereo by that time.