MALVERN has been a leading light in the world of radar since 1942, when two government establishments, TRE and ADRDE, moved from the South Coast to the town.

But radar - the detection of objects, mainly aeroplanes, using radio waves - had in fact been invented some years previously.

Last month, a memorial to the fateful experiment which first proved radar was a practical possibility was unveiled near Daventry, Northamptonshire.

On February 26, 1935, Robert Watson Watt and Arnold Wilkins used the BBC's shortwave transmitter at Daventry to detect an aircraft flying overhead.

Their primitive apparatus could only register the plane's presence, not its position or distance, but nevertheless a new era had dawned.

Cheltenham man Rex Boys, who was a schoolboy in Daventry, thought that such a momentous experiment should not go unmarked and decided to do something about it.

He secured the necessary planning permissions and persuaded QinetiQ, the latter-day descendent of TRE, to fund the project.

The monument, in the field opposite the experiment site, is a large stone from a local quarry, with a metal plaque. The land on which the memorial sits was donated by the farmer who owns it. The plaque was unveiled by Nancy Wilkins, widow of Arnold Wilkins, in front of a gathering of about 80 people from the radar world.

Donald Tomlin, of Malvern, a former RSRE man who was among those present, said: "She spoke strongly and affectionately of the people involved in those early days from the Air Ministry and the Slough Radio Research Station, who went on to found the Bawdsey research station and ultimately TRE and the radar part of ADRDE."

The memorial is about 600 yards along the former B4525 Banbury road, from its junction with the A5, at map reference SP 650 557 (or 4650 2557).