Time and frequency information in telecommunications systems standardized by Federal Standard 1002A

The Federal Standard entitled Time and Frequency Information in Telecommunication Systems establishes the requirements for telecommunications facilities and systems of the Federal government for obtaining Coordinated Universal Time (UTC) coordinated time and frequency reference information based on national time scales maintained by the National Institute of Standards and Technology (NIST) and the US naval Observatory (USNO). The time scales of NIST and USNO are steered to the international UTC time scale maintained by the Bureau International des Poids et Mesures (BIPM) in Paris, France. NIST and USNO also maintain atomic clocks which contribute to the UTC average. The values of UTC promulgated by NIST and USNO are used by the United States Federal Government to obtain standard values of time.<
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