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WWVB Station Outages

 

Since October 29, 2012 at 1500 UTC (9:00 AM MDT), NIST Radio Station WWVB has been broadcasting a phase modulation (PM) time code protocol that has been added to the legacy AM/pulse-width-modulation signal. This enhancement to the broadcast, which has been tested throughout 2012, provides significantly improved performance in new products that are designed to receive it. Existing radio-controlled clocks and watches are not affected by this enhancement, and continue to work as before. A detailed technical description of the new format can be found here.

Disciplined oscillator products that track and lock to the 60 kHz WWVB carrier and were designed to work as frequency standards, will not work with the PM signal and will now become obsolete. A few radio controlled clocks that used information from the carrier – specifically the Spectracom NetClock and receivers manufactured by True Time during the 1970s and 1980s – will no longer be able to read the time code and will also be obsolete. For more information, contact Broadcast Manager Michael Lombardi at michael.lombardi [at] nist.gov or (303) 497-3212.

Broadcast Outages for WWVB

 WWVB Home 2003 Outages 2004 Outages 2005 Outages 2006 Outages 2007 Outages 2008 Outages 2009 Outages
2010 Outages 2011 Outages 2012 Outages 2013 Outages 2014 Outages 2015 Outages 2016 Outages 2017 Outages
2018 Outages 2019 Outages 2020 Outages          

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

Date

MJD Began (UTC) Ended (UTC)
22 September 2021 59479 1423 1609
02 June 2021 59367 0427 0448
30 April 2021 59334 1520 2256
21 April 2021 59325 1459 1823
10 April 2021 59314 2212 2241
30 March 2021 59303 2305 2314
30 March 2021 59303 1920 2005
30 March 2021 59303 0047 0104
26 March 2021 59299 2231 2241
25 March 2021 59298 1500 1535
20 March 2021 59293 0228 0242
14 March 2021 59287 1908 2148
09 March 2021 59282 2037 2043
09 March 2021 59282 2013 2022
11 February 2021 59256 1256 1410
Created November 2, 2010, Updated September 22, 2021