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Replicating UTC(NIST) at Remote Sites



Michael A. Lombardi, Andrew N. Novick, J. Mauricio Lopez-Romero, Rodrigo Ramos


The National Institute of Standards and Technology (NIST) is deploying disciplined oscillators that are referenced to the UTC(NIST) time scale through common-view observations of Global Positioning System (GPS) satellites. We present measurement results from four NIST disciplined oscillators (NISTDOs), three located in the United States, and one located in Concepcion, Chile. These devices replicate the NIST time scale at remote sites and uncertainties of less than 5 ns are demonstrated at all locations. We verified, and in some cases improved the results, by utilizing UTC(CNM), the national time scale of Mexico, as an independent check standard. Further verification was obtained by directly comparing a NISTDO to UTC(NIST) in Boulder, Colorado.
Proceedings Title
Proceedings of 2012 Precise Time and Time Interval (PTTI) Meeting
Conference Dates
November 26-29, 2012
Conference Location
Reston, VA


disciplined oscillator, frequency, time, time scale


Lombardi, M. , Novick, A. , , J. and Ramos, R. (2012), Replicating UTC(NIST) at Remote Sites, Proceedings of 2012 Precise Time and Time Interval (PTTI) Meeting, Reston, VA (Accessed April 18, 2024)
Created November 26, 2012, Updated February 19, 2017