The television link from Manchester to Scotland operated at 4 GHz and thus was the first true SHF route operated by the Post Office. It was found necessary as a means to provide the programme feed for the planned BBC transmitter and was routed so that it passed through, or close to, Leeds, Newcastle and Edinburgh in the expectation that further transmitters or studios might be established in due course.
In sequence from Manchester the sites were:
With the exception of Telephone House and Blackford Hill all sites remained in use as the network developed however later television links were routed via Carlisle with Pontop Pike (Newcastle) and Tinshill (Leeds) effectively becoming branch routes from Carlisle and Manchester respectively. The Manchester SHF site moved “out of town” to Heaton Park in the late 1960s and at Edinburgh a new site at Craiglockhart came into service to replace Blackford Hill.
Each site, other than the Manchester terminal station, used a “pylon” type tower carrying two 10 ft dishes in each direction. A variety of heights of tower was use, Blackcastle Hill being the tallest. Some of the original buildings have survived, probably as “site share” facilities and the original tower at Kirk o’Shotts was still in place in the early 1980s. The design of tower, however, seemed to limit further expansion and replacement structures, together with new buildings of a standard pattern, were provided at all sites during the 1960s.
Unlike the London to Birmingham link which seemed to be used in turn by BBC and ITA, and despite initial consideration of the option, the 1952 link from Manchester was not used when the ITA transmitter at Black Hill (close to Kirk o’Shotts) entered service in August 1957 – a cable connection was provided, albeit routed via Kirk o’Shotts which became a Post Office network switching centre.
An intermediate site at Wooler, between Corbys Craggs and Blackcastle Hill, was considered during initial planing but not used for the original television link. It was added to a subsequent RADAR link which ran over part of the route and eventually entered service around 1967.
The Post Office Chief Engineer’s Report for the year ended 31 March 1950 comments: “To meet the requirements of further television broadcasting announced by the B.B.C. and, in particular, of the Scottish sender at Kirk o? Shotts, an exhaustive survey of the route between Manchester and Kirk o?Shotts was carried out and a specification prepared for a radio relay system between these two points.” In the following year’s report progress was reported: “The specification relating to this system, referred to in the last Report, was issued with invitations to tender. Tenders were received from the General Electric Co. Ltd. and Standard Telephones and Cables Ltd. and the contract was awarded to the latter firm who are proceeding with the manufacture of the equipment. The equipment, which will operate at frequencies around 4,000 Mc/s., will use frequency modulation and employ travelling-wave amplifiers which will illuminate 10 ft. diameter paraboloid reflector aerials through wave guide connexions. The Company has carried out propagation tests over most of
the sections of the link and has demonstrated prototype units of equipment operating in the laboratory. Building construction, mast foundation work, access roads, power supply and telephone line connexion operations are in hand at all sites.”
The 1952 Report confirms the new link had entered service, indeed it had been used ahead of schedule to broadcast coverage of the King’s funeral (15 February 1952). More detail of the completion of the link was also given: “For the Manchester ? Kirk o?Shotts radio television link, a temporary hut […] was erected on the roof of Telephone House, Manchester, and the building for the terminal station at Kirk o?Shotts was completed. Seven of the eight intermediate stations [*] were also completed; one of these [Pontop Pike] was specially constructed of reinforced concrete to withstand possible subsidences and the base of the tower for the paraboloids was so constructed that it can be ?jacked up? if it falls
out of plumb.” * The “missing” station would seem to be Wooler.
By 1953 “The Manchester ? Kirk o?Shotts television relay system has carried traffic on a regular basis throughout the year. The need to complete this system and, at the same time, to preserve continuity of service, imposed a heavy load on the contractors and the Department?s
Clerks of Works. The final acceptance tests were completed in February 1953 and the system will soon operate on a completely-unattended basis. Arrangements have been made to provide equipment that will enable programs to be injected into the system at any of the intermediate repeater stations.”
The 1954 Report mentions the required extension from Kirk o’Shotts towards Aberdeen and that an interim arrangement would be used. “Consideration is also being given to […] the addition of broadband channels on the existing Manchester – Kirk o’Shotts radio link […] to meet future requirements for broadband channels for the I.T.A., the B.B.C second television program [sic] and expansion of the main trunk telephony network.” It appears, however, that this option was not followed in subsequent years. The status of the existing link was noted: “Since 1 May 1953, the intermediate stations of the Manchester ? Kirk of Shotts link have been operated on an unattended basis, leaving staff only at the terminal stations; the performance remains satisfactory and maintenance is now in the hands of the Regions concerned. It is interesting to note that the incidence of faults has been substantially reduced by continuous operation of standby equipment, thus eliminating electrical and thermal surges due to switching.”
The link is not specifically mentioned in the 1955 Report and in 1956 there is confirmation the ITA link to Black Hill would be provided by cable.