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2007 WWVB Broadcast Outages

NIST Radio Station WWVB concluded the test of a experimental advance notification system for daylight saving time (DST) on July 10, 2007. This testing began on June 21, 2007 and involved using bit 54 of the WWVB time code, which has previously been unused. The decision was made NOT to implement the new DST system because of possible adverse effects that it had on some existing radio controlled clocks.

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, 2007 when the signal was off or intermittent for more than 5 minutes.

DateMJDBegan (UTC)Ended (UTC)
12-05-20075443903360433
10-13-20075438619282016
08-10-20075432206000658
07-18-20075429916582125
07-02-20075428316541704
06-27-20075427815501909
06-21-20075427203260424
06-17-20075426810481147
06-17-200754268----0055
06-16-2007542672158----
06-07-20075425808160925
05-07-20075422715352220
04-26-20075421622372258
03-27-20075418613551407
03-06-20075416522512302
02-16-20075414713021357
01-25-20075412511381257
Created February 17, 2016, Updated January 9, 2017