Orolia Spectracom VelaSync 1232, Руководство пользователя

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The NTP throughput statistics data can be utilized to calculate mean values and the stand-
ard deviation.
Example log entries include:
Synchronized to (IP address), stratum=1 : NTP is synchronizing to another
Stratum 1 NTP server.
ntp exiting on signal 15 : This log entry indicates NTP is now indicating to the net-
work that it is a Stratum 15 time server because it is not synchronized to its selected
reference.
Time reset xxxxx s : These entries indicate time corrections (in seconds) applied to
NTP.
No servers reachable : NTP cannot locate any of its configured NTP servers.
Synchronized to PPS(0), stratum=0 : NTP is synchronized using the PPS ref-
erence clock driver (which provides more stable NTP synchronization).
Oscillator Log
Displays log entries related to oscillator disciplining. Provides the calculated frequency
error periodically while synchronizing to a reference.
GPS Qualification Log
If VelaSync is connected to a GNSS antenna and is tracking satellites, this log contains a run-
ning hourly count of the number of GNSS satellites tracked each hour. This history data
can be used to determine if a GNSS reception problem exists and whether this is a con-
tinuous or intermittent reception issue.
GNSS reception may be displayed as cyclic in nature. A cyclic 12 hour pattern of decreased
GNSS reception typically indicates that the GNSS antenna has an obstructed view of the
horizon. The GNSS satellites are in a 12-hour orbit, so if part of the sky is blocked by large
obstructions, at the same time every day (at approximately 12 hour intervals), the GNSS
reception may be reduced or may vanish altogether. If this occurs, the antenna should be
relocated to afford it an unobstructed view of the sky.
Every hour (displayed in the log as UTC time), VelaSync counts the total number of satel-
lites that were tracked during that hour. The GNSS qualification log shows the number of
satellites that were tracked followed by the number of seconds that the particular number
of satellites were tracked during the hour (3600 seconds indicates a full hour). The num-
ber to the left of the “=” sign indicates the number of satellites tracked and the number to
the right of the “=” sign indicates the number of seconds (out of a total of 3600 seconds in
an hour) that the unit was tracking that number of satellites. For example, “0=3600” indic-
ates the unit was tracking 0 satellites for the entire hour, while “0=2700 1=900” indicates
the unit was tracking one satellite for 900 seconds, but for the remaining portion of the
hour it was tracking zero satellites.
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CHAPTER
4
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VelaSync 1232 User Manual Rev. 4
4.7 Quality Management