Jodrell Bank Observatory: Lovell Telescope

Radio Telescope

The Lovell Telescope at Jodrell Bank Observatory is a radio telescope constructed between 1952 and 1957, designed by Sir Charles Husband for Sir Bernard Lovell. It has undergone alterations in the periods 1967-71 and 1976, as well as modifications in the 21st century.

The structure comprises a circular paraboloid dish constructed of welded steel plates, measuring 250 feet in diameter, mounted within a cylindrical steel framework. This framework is supported on bearings at the top of two triangular legs, each 56 metres tall, known as the red and green towers. The entire assembly runs on two concentric tracks of double rails with an overall diameter of 107 metres, supported by a concrete bed of the same diameter. The tracks are bolted to the concrete bed and incorporate four-wheeled bogeys at the base of each structural member.

The receiving surface is an extended central lattice mast supporting an interchangeable receiver, positioned forward of the plane of the front of the dish. The towers are linked at the base by a lattice diametral girder with raking braces. The green tower (to the right when viewed from the south) has five floors of rooms at its top, clad in corrugated steel with windows to each floor. The red tower has three storeys, also with windows. Both towers contain a central splayed space-frame with an open central lift-core and stair. Two steel beams connected by cross-members form a forward-projecting raking support.

On the inner face of the covered structures can be seen the edge of the circular trunnion bearings which transfer the load from the cylindrical support to the towers. A rectangular emergency generator house, known as the Marconi Hut, stands on the upper members of the diametral girder and is clad in corrugated steel with two multi-paned windows, accessed by stairs. Within the centre of the girder, above the central pivot, stands an equipment house of corrugated steel with two tall multi-paned windows. In front of the girder is a frame of approximately 1971 with two main legs mounted on two four-wheeled bogeys, with two curved support girders projecting forward to connect with the perimeter of the dish. A floating metal stair provides access from the ground.

The perimeter of the dish is covered by a substantial rim which covers the gap between the current receiving surface and the original. From all viewing angles the structure demonstrates its complex engineering with exposed steel lattice work, radial spokes linked laterally to create concentric rings when viewed from below, and semi-circular support girders linked by cross-member arrangements.

A swinging laboratory is located adjacent to the dish, comprising a small rectangular corrugated-steel cabin with pitched roof. Each long side has a central nine-paned window, while each end has a circular pivot. The green end has a small enclosed landing with a door where the access stair meets it.

At the centre of the concrete bed is an annular chamber beneath the main pivot, with smooth concrete walls. This chamber is accessed via steps in the concrete bed to the north of the central pivot and gives access to a tunnel running to the south-east which links the dish to its control room. The tunnel has plain shuttered concrete walls and extends beneath a later western control room extension.

In the upper levels of the towers, the steel frame is exposed but the corrugated cladding is sheet-lined. Metal windows and light fittings are original. These upper levels contain the motors and gearing of the elevation drive which moves the dish via former battleship gun-turret racks. The top floor houses a very large block and tackle and the trunnion bearings, connected to the frame of the dish by steel cones. The lifts of the towers have been replaced.

The equipment house retains much original 'Brush' electrical power equipment and analogue control and monitoring equipment. Central in the room is a tall metal drum containing the cable-turner, which allows the cables entering the dish to rotate through 420 degrees. The Marconi Hut contains a modern diesel generator.

The annular chamber contains modern cabling, and the tunnel contains cabling in wall trays with some modern sealant repairs.

The telescope stands in former farmland, surrounded by numerous research and support buildings, mainly positioned to the east and south.