Radio Communications by Very Short Electric Waves

Abstract

THE Marchese Marconi delivered the Friday evening discourse at the Royal Institution of Great Britain on December 2 and described his experimental investigations during the past year or two with electric waves less than one metre in wave-length. The systematic investigation of the properties and characteristics of these very short waves was taken up in view of the advantages which they seemed to offer in the field of practical radio communication, on account of the small dimensions of the apparatus necessary for emitting and receiving a considerable amount of electrical energy, combined with the freedom from interference due to electrical disturbances on such wave-lengths. At the commencement of his lecture, the Marchese Marconi referred to the fact that in 1896 he demonstrated the possibilities of short-distance wireless communication on a wavelength of about 30 cm., using a ‘spark’ transmitter and suitable reflectors. In the more recent work, a thermionic electron oscillator was employed, operating on the principle first demonstrated by Barkhausen and Kurz as a means of producing oscillations corresponding to wave-lengths of less than 100 cm.