The Super-Heterodyne-Its Origin, Development, and Some Recent Improvements

This paper describes the development of the super-heterodyne receiver from a wartime invention into a commercial form of broadcast receiver apparatus now available to the general public. The success of the development is due to the low filament consumption vacuum tube and to the reduction in the number of tubes required by self-heterodyning, reflexing, and improvement in transformer design. Instances are cited of trans-Atlantic and trans-continental reception of broadcast stations by completely portable sets constructed in accordance with the methods described.