Development of Precision Time and Frequency Systems and Devices at Apl

APL's entry into research, development, testing, and fabrication of precision time and frequency devices was occasioned by its development of a high-quality, spaceborne oscillator for the Transit navigation satellite program. Later, this effort branched out into atomic frequency standards and other innovative frequency standards such as the super conducting cavity stability oscillator and trapped ion devices. As an auxiliary operation, APL maintains and operates a Time and Frequency Standards Laboratory containing in-house standard time and frequency devices that are tracked against other time standards that contribute data for the international calibration of the basic unit of time, the second.