Portable Alternating-Current Operated Heterodyne Beat Apparatus of Unusual Frequency Stability

Abstract

In the heterodyne beat method of measuring dielectric constants of vapors or very dilute liquid solutions, it is difficult to eliminate frequency drift in the one oscillator. Apparatus which will almost completely eliminate this drift is described; it has the further advantage of operating entirely on a.c., thus eliminating much inconvenience and appreciable battery upkeep. The apparatus is portable, and therefore useful as a laboratory piece as well as for research.