L'histoire du "radar ", les faits
The history of the "radar", the facts

" ....au mois de septembre 1940, la mission britannique, dirigée par Sir Henry Tizard, apporta un magnétron.... "

SYSTEM FOR OBJECT DETECTION AND DISTANCE MEASUREMENT

United States Patent  Office   N° 2,433,838
Filed     Dec. 30, 1939
in France   Dec. 1, 1938

Maurice Elie, Henri Gutton, Jean Jacques Hugon, Maurice Ponte

Application

"Apparatus for detecting obstacles by the reflection from said obstacles of very short electro-magnetic waves
comprising in combination a sender and a receiver..."