Quartz-Crystal Clock

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Quartz-Crystal Clock


an instrument for exact time measurements. Its operation depends on the oscillations of a quartz-crystal oscillator. The accuracy of the time readings is determined by the stability of the oscillation frequency of the oscillator and by its quality factor. Since the frequency v of a precision quartz-crystal resonator depends on temperature (Δv/v≦ 10-8 per degree C), the resonator is placed in a temperature-controlled enclosure with an accuracy of 0.001°C.

In addition to a quartz-crystal oscillator, a quartz-crystal clock also contains oscillation frequency converters (dividers and multipliers); a synchronous motor that drives the clock hands (or a digital counter); and a contact device for the transmission of exact time signals. Quartz-crystal clocks are usually equipped with devices that emit a set of standard frequencies for purposes of measurement. For exact time service two or three quartz-crystal clocks are used simultaneously; their frequencies are compared with each other, with a quantum frequency standard, and with data derived from astronomical observations.


Klemens, G. “Etalony vremeni i chastoty.” Uspekhi fizicheskikh nauk, 1957, vol. 62, no. 4.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.