X-Nico

5 unusual facts about cavity magnetron


Cavity magnetron

The modern 'resonant' cavity magnetron tube was invented by John Randall and Harry Boot in 1940 at the University of Birmingham, England.

In 1937-1940 a multi-cavity magnetron was built by the British physicist Sir John Turton Randall, FRSE, together with a team of British coworkers, for the British and American military radar installations in World War II.

The first form of magnetron tube, the split-anode magnetron, was invented by Albert Hull in 1920, but it wasn't capable of high frequencies and was little used.

In 1940, at the University of Birmingham in the United Kingdom, John Randall and Harry Boot produced a working prototype similar to Hollman's cavity magnetron, but added liquid cooling and a stronger cavity.

Non-neutral plasmas

More prosaically, pure electron plasmas are used to produce the microwaves in microwave ovens, via the magnetron instability.


Canada and weapons of mass destruction

Materials included the cavity magnetron which was essential to RADAR, British information related to the German Enigma machines, Jet Engine designs as well as "Tube Alloys".

SCR-584 radar

Edward George Bowen had prepared for just this moment, and presented one of the earliest cavity magnetrons to the assembled researchers.


see also

Albert Hull

However, during World War 2 John Randall and Harry Boot built on Hull's concept to develop the modern cavity magnetron, the first device which could produce high power at microwave frequencies, and the resulting centimeter-band radar proved a crucial advantage for the Allies in aerial warfare.