The history of telecommunications -Lévy page 673

In 1916 is responsible for laboratories military radio on the Eiffel Tower. In June of that year produces a transmitter for broadcasting by 1.5 Kw always on the tower. This period studied modulation amplitude with ultrasonic frequencies to obtain secret communications. For get this oscillator uses an ultrasonic frequency.. 1917 deposits patent No. 493660 in which demonstrates the feasibility of using radio receiver in a local oscillator which improves the performance of the same especially for high frequencies. Next a patent filed on October 1, 1918 with the number 506297 exposes diagram of a receiver superhetherodyne.

Lucien Lévy