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Omega clock timing problems |
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Problems with older Omega Clocks
Timing Update - PGC fixed 97-10-27
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On Oct 23/97 at 21:10 the timing at station PGC was switched from Omega to
GPS. The time correction for PGC will now be 0.0 s. At the same time, the
transmission gain was changed from 2**8 to 2**5, which has triggered a change
in the response.
Timing Update - INK fixed 97-10-17
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On Oct 16/97 at ~18:00 the timing at station INK was switched from Omega to
GPS. The time correction is now 0.0 s.
Timing Alert! 97-10-05
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The shutdown of the OMEGA time service at 03 UT Tuesday September 30 caught
us unawares. Since that time, the clocks at CNSN stations DAWY, DRLN, EDM,
FCC, FRB, GAC, INK, PGC, SCHQ, and WHY have been drifting and their timing is
uncertain. We have a plan to upgrade the clocks of these stations to GPS, but
this will take some time.
By local convention, we flag a station having unknown timing with a time
correction of 999.9 seconds. Unfortunately, when this gets translated to the
GSE format, which lacks a separate time correction field, this value gets
*applied*. This in effect means that the time of the data returned is ~16.6
minutes after what was requested, +/- the actual time correction. For SEED
format data, the time correction is logged but not applied. Note that certain
programs like rdseed read and apply the time correction when converting
formats.
Please use data from the above list of stations with caution until further
notice. We are sorry for the inconvenience this may cause.
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