Robert Watson - Watt demonstrated a working prototype .
Robert Watson - Watt patented the device in 1935 ( British Patent GB593017 ) The device served as the base for the Chain Home network of radars to defend Great Britain .
Robert Watson - Watt demonstrated a working prototype and patented the device in 1935 ( British Patent GB593017 ) The device served as the base for the Chain Home network of radars to defend Great Britain .