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Welcome to Time and Frequency


Science > Time and Frequency

Home of the nation's atomic time scale, UTC(NPL), NPL is the focus for time and frequency measurements in the UK. Our responsibilities are both international, in contributing to the international time scale UTC, and national, in providing the UK time scale related to UTC against which time and frequency broadcast signals in the UK can be monitored. Funded by the National Measurement System Directorate at Department of Trade and Industry, NPL follows a three year National Measurement System Programme for Time and Frequency Measurement.

Link to Optical Frequency Standards Home Page

Radio Mast

The MSF signal is moving

New to Time and Frequency, select this link to view whole list

MSF is the 60 kHz signal which broadcasts the national time standard for the UK. From the 1st April 2007 the MSF service will transfer to Anthorn, until then it will continue to be transmitted from Rugby.


Time and Frequency at NPL

  • Time and Frequency Club
    The last meeting was held on 14th September 2006 at NPL and will covered updates on the Galileo project, information on the changes to MSF and other industry related talks. Find out more regarding club activities and how you can join.

  • No Leap Second in 2006
    The organisation responsible for monitoring changes in the Earth's rotation has announced that there will be no leap second in the international time scale Coordinated Universal Time (UTC) at the end of December 2006. For more information about leap seconds, click on the link above.

The Measurement of Time

Measurement of time

When does British Summer time start? How have people recorded time for the last 2000 years? When were atoms first used to keep time? Information about these and other questions, plus suggested general interest reading material, children's books and relevant scientific journals can be found by following the "Measurement of time" link on the left.

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