[IGSMAIL-4406]: NRC1: Clock Change MID-DAY - 15:00 UTC, 03May28 (DOY148)

[Delahunt, Stephen]

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IGS Electronic Mail      28 May 12:26:26 PDT 2003      Message Number 4406
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Author: Stephen M. Delahunt

IGS Site:   NRC1
DOMES # 40114M001
Agency:    Natural Resources Canada (NRCan) ...formerly EMR
Location:   Ottawa, Ontario
Country:    CANADA

ADVISORY: The current Hydrogen Maser clock was taken off-line at 15:00 UTC,
03May28 (DOY148).
                   NRC1 data for the remainder of 03May28 (DOY148) will not
be submitted to the IGS.
                   Hourly data submissions will resume tomorrow 03May29
(DOY149).
                   A different Hydrogen Maser clock was introduced at this
site, between 15:00 and 16:00 UTC.
                   Tracking was not terminated and between active-maser
disconnect/reconnect the receiver 
                   tracked using internal crystal with clock steering.  

RECOMMENDATION:  Do not use NRC1 data for 03May28 (DOY148), beyond 15:00 UTC