Communications: The world versus RCA: Circumventing the superhet: Because a clearly superior tuning circuit was denied them by a patent award, manufacturers developed both clumsy and elegant alternatives

For about six years during the Roaring Twenties, fledgling radio manufacturers engaged in a desperate competition for customer acceptance. The manufacturer that made it easy for listeners to tune in with a single dial could offer a far more attractive product than one that required manipulation of two, three, and even four dials. And so the engineers at such companies as Atwater Kent, Magnavox, and Crosley struggled to find ways to alter the characteristics of multiple tuning circuits with one control knob. For Radio Corp. of America of New York, as RCA was then known, the solution came readily. The company owned the patents for Edwin H. Armstrong´s superheterodyne circuit, which had two manually operated tuning circuits. This superior tuning circuit was protected by a patent award. The author describes the various alternatives other manufacturers developed to solve the problem.