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Physical Measurement Laboratory / Time and Frequency Division

Time Realization and Distribution Group

This page is no longer being updated and the information may be out of date.

2004 WWVB Broadcast Outages

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During normal operation, the 60 kHz signal from WWVB is transmitted 24 hours per day, 7 days a week. The table includes periods since January 1, 2004 when the signal was off or intermittent for more than 5 minutes.

DateMJDBegan (UTC)Ended (UTC)
12-07-20045334612421329
11-01-20045331003400433
09-02-20045325006120736
08-06-20045322322432258
07-09-20045319511211154
07-05-20045319119172004
07-04-20045319019152025
06-08-20045316409451045
03-06-20045307013461500
01-02-20045300610181113
01-01-20045300512321328
Time and frequency
Created February 17, 2016, Updated September 29, 2025
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