[time-nuts] WWV Clock

Mike Monett xde-l2g3 at myamail.com
Mon Nov 2 10:10:55 UTC 2009


  Replying to  my own post, there are two bits that  indicate daylight
  saving time  changes.  Here's a paragraph  from  page  27, Lombardi,
  "NIST Time  and Frequency Services", NIST  Special  Publication 432,
  2002 Edition:

  "Daylight saving  time (DST) and standard time  (ST)  information is
  transmitted at seconds 57 and 58. When ST is in effect, bits  57 and
  58 are  set to 0. When DST is in effect, bits 57 and 58  are  set to
  1."

  "On the day of a change from ST to DST bit 57 changes from 0 to 1 at
  0000 UTC, and bit 58 changes from 0 to 1 exactly 24 hours  later. On
  the day  of a change from DST back to ST bit 57 changes from 1  to 0
  at 0000 UTC, and bit 58 changes from 1 to 0 exactly 24 hours later."

    <http://tf.nist.gov/timefreq/general/pdf/1383.pdf>

  So it  seems the HTAWI receives the bits correctly, but it  does not
  act on them until both are the same.

  Some relevant articles are available:

  NIST Special Publication 432, 2002 Edition
  NIST Special Publication 250-67
  WWVB RCC Recommended Practices 2009

    <http://tf.nist.gov/stations/hflibrary.htm>

  Regards,

  Mike Monett



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