IEEE President Dr Tom Coughlin and University of Birmingham Vice Chancellor Professor Adam Tickell shake hands by the plaque
Celebrating the cavity magnetron

Presented by the Institute of Electrical and Electronics Engineers (IEEE), the Milestone plaque celebrates the work of John Randall, Harry Boot and James Sayers, whose research on the cavity magnetron at the University played an important part in Allied success in World War II. More prosaically, it remains a key piece of technology used to power microwave ovens.

The group developed the device during a period of collaboration in the University between 1939 and 1941. The magnetron is a radio source that operates at microwave frequencies, and it was initially developed to power early radar systems.

A cavity magnetron

The version invented by Randall, Boot and Sayers, was higher powered than previous versions, and portable. It was rapidly adopted by Allied forces during World War II for use in radar equipment on board Allied planes to detect enemy aircraft and vessels.

The high-power microwave pulses generated within the magnetron, that were a game changer for radar technology, later became fundamental to the development of microwave ovens and other industrial heating applications.

Professor Bill Chaplin, Head of the School of Physics and Astronomy at the University of Birmingham, said: “The work done by John Randall, Harry Boot and James Sayers here at the University of Birmingham was creative, practical and ingenious. Their invention provided a cornerstone of modern technology and demonstrates University research at its best – much as the work we are doing here today in fields such as quantum technology will underpin future everyday technologies.”

The work done by John Randall, Harry Boot and James Sayers here at the University of Birmingham was creative, practical and ingenious, and demonstrates University research at its best.

Professor Bill Chaplin, School of Physics and Astronomy

The Milestone proposer, Professor Peter Grant, Life Fellow of the IEEE, said: “Milestone plaques honour significant and historic technical advances around the world. We’re delighted to be celebrating this important achievement with this plaque and hope it will serve as inspiration for current and future researchers in the field."

This Milestone was approved through a rigorous process by the IEEE History Committee and Board of Directors and joins more than 250 others marking pioneering achievements made by scientists and engineers around the world, including the invention of the laser semiconductor; the first public demonstration of television; and the invention of the bar code.

The Milestone Plaque was unveiled by University Vice Chancellor Professor Adam Tickell and IEEE President Dr Thomas Coughlin and the ceremony followed by a comprehensive technical seminar covering the evolution of these developments from before the Second World War to the present day.