Historical Review of Ultra-Short-Wave Progress

This paper is a historical review up to the year 1931 of the more significant experiments with radio ultra-high frequencies and ultra-short waves. Developments are classified, in accordance with the type of oscillation generator employed, under four main heads: spark oscillators, regenerative oscillators of conventional type, electronic oscillators of Barkhausen-Kurz and Gill-Morrell type, electronic oscillators of the magnetron type. Within these four divisions arrangement is chronological.