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General Interest T&F Publications

The table below includes a list of general interest time and frequency publications authored by NIST personnel. These publications are made available as PDF files that can be viewed using the Adobe Acrobat Reader.


CategoryTitle and DescriptionLead AuthorPlace of Publication
IntroductionFrom Sundials to Atomic Clocks: Understanding Time and Frequency

Originally published in 1977, this full-length book provides a comprehensive, easy-to-understand introduction to the field of time and frequency. Readers of nearly all ages and educational backgrounds should find it enjoyable. 306 pages.
JespersenNIST Monograph 155, 1999
NIST Time SignalsNIST Time and Frequency Services

An illustrated, comprehensive overview that describes NIST Radio Stations WWVB, WWV, and WWVH work, and how you can use them. The NIST computer time and frequency calibration services are also briefly discussed. 80 pages.
LombardiNIST Special Publication 432, 2002
 How Accurate is a Radio Controlled Clock?

A detailed discussion of the accuracy of WWVB radio controlled clocks. It reviews the factors that limit the accuracy of a radio-controlled clock, including the path delay between the radio station and the clock, how accurately the clock synchronizes with the signal, and how accurately the clock keeps time between synchronizations. 4 pages.
LombardiThe Horological Journal, March 2010
 WWVB Radio Controlled Clocks: Recommended Practices for Manufacturers and Consumers

A booklet containing recommended practices for WWVB radio controlled clock manufacturers, plus tips for consumers attempting to troubleshoot reception problems. 64 pages.
LombardiNIST Special Publication 960-14, 2009
 Radio Controlled Wristwatches

A general interest article about the various types of radio controlled wristwatches. 5 pages.
LombardiThe Horological Journal, May 2006
 Radio Controlled Clocks

A discussion of the history of radio controlled clocks, how they work, and the types of radio signals that control them. 18 pages.
Lombardi2003 NCSLI Conference
Atomic StandardsNIST Primary Frequency Standards and the Realization of the SI Second

A detailed overview of the primary frequency standards at NIST that covers their history, design, and the theory of operation. Includes color photographs of all of the NIST primary cesium standards and an extensive list of references. 17 pages.
LombardiMeasure: The Journal of Measurement Science, December 2007
 Standards of Time and Frequency at the Outset of the 21st Century

A nicely written overview that examines the first fifty years of microwave atomic clocks, and the ongoing progression towards optical standards. 7 pages.
DiddamsScience, November 2004
 Time Measurement at the Millennium

A discussion of recent developments in atomic timekeeping, written for the NIST centennial in 2001. Winner of the 2001 NIST Condon award for best paper. 6 pages.
BergquistPhysics Today, March 2001
 Primary Atomic Frequency Standards at NIST

A discussion of the primary atomic frequency standards that have been developed at NIST. Includes some historical information, but is mainly about recent, current, and possible future standards. 17 pages.
SullivanNIST Journal of Research, January-February 2001
 Accurate Measurement of Time

Excellent general interest article about atomic timekeeping. 8 pages.
ItanoScientific American, July 1993
Computer TimekeepingNIST Computer Time Services: Internet Time Service (ITS), Automated Computer Time Service (ACTS), and Web Sites

A thorough discussion of how the NIST computer time services work. 79 pages.
LevineNIST Special Publication 250-59, May 2002
GPS Time TransferTime and Frequency Dissemination: Advances in GPS Transfer Techniques

An overview of the various ways GPS is used for time and frequency applications. Written by authors from NIST and the United States Naval Observatory (USNO). 7 pages.
ParkerGPS World, November 2004
 The Use of GPS Disciplined Oscillators as Primary Frequency Standards for Calibration and Metrology Laboratories

A discussion of the use of GPS disciplined oscillators (GPSDOs) in calibration laboratories. It discusses how GPSDOs work, how measurement traceability can be established with a GPSDO, and how their performance can vary significantly from model to model. 10 pages.
LombardiMeasure: The Journal of Measurement Science, September 2008.
 Time and frequency distribution using satellites

A comprehensive discussion of how time and frequency information is distributed through GPS and other satellite systems. 46 pages.
LevineReports on Progress in Physics, July 2002
 Time and Frequency Measurements using the Global Positioning System (GPS)

An overview of the various types of GPS measurements, including the one-way, two-way, and carrier phase techniques. Includes a discussion of traceability. 8 pages.
LombardiCal Lab Magazine, July-September 2001
HistoryThe Evolution of Time Measurement, Part 1: Celestial, Flow, and Mechanical Clocks
The Evolution of Time Measurement, Part 2: Quartz Clocks
The Evolution of Time Measurement, Part 3: Atomic Clocks
The Evolution of Time Measurement, Part 4: The Atomic Second
The Evolution of Time Measurement, Part 5: Radio Controlled Clocks

A five-part series of short articles about the history of clocks and timekeeping. The articles range from 4 to 8 pages in length, and attempt to focus on the most significant events in the history of timekeeping, by discussing both the advances in technology and the people involved. Illustrated with color photos. 
LombardiIEEE Instrumentation and Measurement Magazine, August 2011 - April 2012
 Time and Frequency Measurement at NIST: The First 100 Years

A history of time and frequency activities at NIST, written for the NIST centennial in 2001. 14 pages.
Sullivan2001 IEEE Frequency Control Symposium
MetrologyCharacterization of Clocks and Oscillators

A collection of published papers assembled as a reference for those involved in characterizing and specifying high-performance clocks and oscillators. Includes extensive information about measurement techniques and data analysis. 352 pages. 
SullivanNIST Technical Note 1337, 1990
 Time and Frequency Users Manual

A detailed, easy-to-read overview of time and frequency measurements. Includes information about quartz and atomic oscillators, and the various radio signals used as measurement references. Outdated in some areas, but still useful. 160 pages.
KamasNIST Special Publication 559, 1990
 Time and Frequency Measurement

A collection of classic time and frequency papers published by authors from NIST and elsewhere. Includes a comprehensive bibliography. 143 pages.
HackmanAmerican Associations of Physics Teachers Publication, 1996
 Introduction to time and frequency metrology

An introduction to the principles and concepts of time and frequency metrology. 30 pages.
LevineReview of Scientific Instruments, June 1999
 Fundamentals of Time and Frequency

An overview of time and frequency metrology intended for non-specialists. 18 pages.
LombardiThe Mechatronics Handbook, 2001
 Legal and Technical Measurement Requirements for Time and Frequency

An overview of time and frequency requirements for various technologies and applications. 10 pages.
LombardiMeasure: The Journal of Measurement Science, September 2006
 Handbook of Frequency Stability Analysis

An excellent reference source that covers the statistics used for the analysis of time and frequency data. It also provides a brief overview of measurement techniques. 136 pages.
RileyNIST Special Publication 1065, 2008
 Stopwatch and Timer Calibrations

A NIST recommended practice guide that describes several ways to calibrate stopwatches and timers. 82 pages.
GustNIST Special Publication 960-12, 2009




Created May 17, 2010, Updated November 7, 2016