Broadcasting House, Plymouth

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Following the decommissioning of the SHF link from Plymouth to North Hessary Tor, the
Plymouth BH showing the old building. The OB Room was bottom left at the foot of the mast.
Plymouth BH mast was reequipped with a panning head and dish feeding the waveguide down to the OB room below. OB receiver head units could therefore be easily installed per occasion and coupled to the waveguide via a circulator.

Up to this time, OBs into BH required a hydraulic hoist vehicle such as an Eagle Tower to raise a dish to over 60 feet in order to clear local obstructions, including trees and buildings. If the dish had been left panned up in a particular direction on the last OB and needed no re-panning, then only one engineer was required to staff the OB. This eventually saved the hydraulic hoist vehicle and driver, the radio link vehicle and driver, and a technical assistant (engineer) per day. For a programme such as Match of the Day from Plymouth Argyle this was a considerable saving. Around 1990 a rotator with dual feeds (7GHz and 2GHz) was installed, offering fast news OB access with only one person required. Later these features were largely displaced by satellite technology.

However, it can be seen from this Plymouth BH photograph that the mast had one major drawback for us youngsters whose job it was to shin up the ladder and pan the dish. The higher you went, the thinner the mast became. In those days one didn’t have the harness with running line which Health and Safety enthusiasts later decreed was obligatory. All we had was a typical P.O. engineer’s leather belt with compartments for tools, stretching around one’s girth and also around the mast, which was quite slim at the top with very little to lean against.

As one climbed, and the mast was only around 70 feet high, your hands could be used for a hold, but on reaching the top and strapping oneself on, your hands were then required to shift the large ring nut so as to allow the dish to be panned. In a Force Something gale this was no small task, and included the risk several of us experienced of the 4 foot diameter dish being caught by the wind, spinning round and whacking us on the head. Fortunately, all of us had the presence of mind to duck in time. During winter months, the panning head lubricating grease hardened up and required a big spanner or similar large object to encourage the locking ring to free up so that panning could occur. At this point you grabbed hold of the dish with both hands and pushed…

Sometimes one appreciates the march of automation.

--Oldcommsboy 15:16, 20 August 2013 (PDT)