BBC North Hessary Tor -

The site for the BBC VHF radio and television Devon and South-West England transmitting station was decided upon only after very careful consideration and tests at two sites.

One was at Horner Down and the other, which was finally decided upon, at North Hessary Tor near Princetown on Dartmoor.

[Shortly before the Public Inquiry held at Exeter in September, 1953, to investigate the BBC’s proposal to build at North Hessary Tor, it was decided to carry out tests from a further site, King Tor Halt, about ¾ mile (approx. 1km) s.w. of North Hessary Tor site. These tests were made to determine whether King Tor Halt might in any way be a satisfactory alternative to North Hessary Tor in the event of the proposals for the use of North Hessary Tor being rejected. The report with the addition of King Tor Halt is here.]

The meticulous selection process for the BBC VHF radio and television transmitting station in Devon and South-West England involved careful consideration and extensive testing conducted at two potential sites.

One of the prospective locations under examination was Horner Down. However, after thorough evaluation, the decision ultimately favoured the site at North Hessary Tor near Princetown on Dartmoor, positioned approximately thirteen miles north-north-east of Plymouth. The North Hessary Tor site proved to be the sole suitable option that could adequately cover Plymouth and its environs while also serving the majority of Cornwall, the Torbay district, and Exeter. However, the proposal to construct a broadcasting station featuring a towering 500-ft mast within the confines of the Dartmoor National Park faced significant opposition from the Dartmoor Preservation Society. As a result, a public inquiry was convened in Exeter to address the matter. Following the inquiry, a favourable decision was reached in support of the BBC, leading to the acquisition of the North Hessary Tor site.

Situated at an elevation of 1650 ft, the selected site initially housed a temporary station that commenced operations on 17th December 1954. The temporary setup employed an aerial system consisting of individual dipoles for vision, with one serving as the primary and another as a reserve, along with a separate dipole for sound transmission. These aerials were affixed to a 150-ft square-section mast. The vision transmitter employed was a converted television outside broadcast transmitter, originally used back in 1936 for the coverage of the coronation. It boasted an output power of 1 kW, and a modified ET 4336 transmitter served as a backup. Similarly, modified ET 4336 transmitters were deployed for television sound transmission, with one in active service and another held as a spare. The programme content was obtained through direct reception from Wenvoe. Both the temporary and eventual permanent stations operated on Channel 2, utilising vertical polarisation and offsets of -16.875 kHz for vision and -20 kHz for sound.

The permanent station established at North Hessary Tor closely resembled earlier medium power stations in its design and specifications. Notably, great care was taken to ensure that the building’s elevation harmonised seamlessly with the natural landscape of the surrounding area. The permanent station’s construction was completed in May 1956, marking a significant milestone in the project. The fully operational permanent mast and station were unveiled on 7th August 1956, heralding a notable advancement in 405-line television transmissions with a maximum output of 15 kW for vision, measured in terms of effective radiated power.