History of telecommunications -Lévy page 674





	Lucien Lévy

	Paris March 11, 1892 in Paris May 24, 1965


	Biographical notes




	He graduated in engineering at the Ecole Supérieure de Chimie et Physique Paris at the end of the First World War. In 1916 is responsible for laboratories radio on the Eiffel Tower. In June of that year produces a transmitter for broadcasting by 1.5 Kw always on the tower.
	During this period studied modulation amplitude with ultrasonic frequencies to obtain secret communications. To achieve this oscillator uses an ultrasonic frequency.
	Thanks to these requirements sees the possibility of using a local oscillator on the receiver getting agreement on a carrier and an agreement on the frequencies generated by the beat frequency range.
	In August 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. A subsequent patent filed on October 1, 1918 with the number 506297 exposes diagram of a receiver superhetherodyne.