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The Reach and Impact of the Remote Frequency and Time Calibration Program at NIST



Michael A. Lombardi


The National Institute of Standards and Technology (NIST) has offered and provided remote frequency and time calibration services to customers for more than three decades. These services continuously compare a customer's primary frequency and/or time standard to UTC(NIST), the U.S. national standard for frequency and time. They differ from traditional calibration services in at least two important ways. The first difference is that customer does not send the device under test to NIST. Instead, NIST sends equipment to the customer that automates the measurements and returns the results via a network connection. The second difference is that the calibration never stops. New measurement results are recorded 24 hours per day, 7 days a week. This allows customers to continuously establish traceability to the International System (SI) via UTC(NIST) without ever disturbing or moving their standard. Since their inception, these services have evolved to meet the frequency and time requirements of customers in a variety of public and private sectors. Initially, most of the customers were calibration and metrology laboratories, primarily located at U. S. military installations and at defense contractor sites. Those customers remain an integral part of the customer base, but the reach of the services now extends to research laboratories, the aerospace industry, the energy industry, electronics and instrument manufacturers, and most recently, to financial markets and stock exchanges. This paper discusses the reach and impact of the NIST remote frequency and time calibration services by describing how they work, their calibration and measurement capabilities, their quality system, and the needs and requirements of the customers that they serve.
Proceedings Title
Proceedings of the 2018 NCSL International Workshop and Symposium
Conference Dates
August 25-27, 0018
Conference Location
Portland, OR
Conference Title
2018 NCSL International Workshop and Symposium


accreditation, calibration, metrology, traceabillity, uncertainty
Created August 27, 2018, Updated February 1, 2019