While we now think of a magnetron as a microwave oven component, they are important in many microwave devices including radar. They are interesting because all they can do is oscillate.

The film discusses the function and operation of microwave oscillators in radar systems, focusing on the importance of oscillators like the magnetron and reflex velocity modulated tubes.

Forged in the fighting of World War II, the cavity magnetron was the heart of radar signals used to identify attacking German forces. The magnetron itself was truly an international effort ...

Invented during the height of the Battle of the Atlantic, the cavity magnetron resembles the vacuum ... than the radio waves previously used for radar defences. The post-war period saw a ...