Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

WWVB: A Half Century of Delivering Accurate Frequency and Time by Radio



Michael A. Lombardi, Glenn K. Nelson


In commemoration of its 50th anniversary of broadcasting from Fort Collins, Colorado, this paper provides a history of National Institute of Standards and Technology (NIST) radio station WWVB. The narrative describes the evolution of the station, from its origins as a source of standard frequency, to its current role as the source of time-of-day synchronization for many millions of radio controlled clocks.
Journal of Research (NIST JRES) - 119.004
Report Number


broadcasting, frequency, radio, standards, time


Lombardi, M. and Nelson, G. (2014), WWVB: A Half Century of Delivering Accurate Frequency and Time by Radio, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 13, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created March 12, 2014, Updated November 10, 2018