Precision Frequency Control for Military Applications

The paper discusses progress made in the field of frequency control over the past years, with emphasis on the contributions of the U. S. Army Signal Corps. The entire field is reviewed, including piezoelectric resonators and devices using atomic and molecular spectral lines. Several accomplishments which are thought to be of special importance are discussed in greater detail. These subjects include, among others: Properties of synthetic quartz, aging prediction of crystal units, new methods of temperature compensation for crystal units, piezoelectric crystals for the VHF range, measurement methods for piezoelectric resonators, cesium-beam frequency standards, ammonia maser, and gas cell devices.