Calibration of high precision oscillators using the TV line frequency as a frequency standard

This paper describes a method for the calibration of high precision oscillators using the received TV line frequency, multiplied to 1 MHz, as a frequency standard. Since the TV system is synchronized by an atomic frequency standard, the TV line frequency preserves the excellent long-term frequency stability of the atomic reference. The phase comparison between the standard frequency and frequency of the oscillator to be calibrated is performed at 1 MHz. A complete schematic diagram of the linear phase comparator is also presented. The linearity of the comparator itself was found to be of the order of 0.1% or better. A relative frequency difference of the order of 10/sup -11/ could be measured over a period of /spl ap/1000 seconds.