Spectracom VelaSync 1225, User Manual

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Every hourly entry in the log also contains a quality value, represented by “Q= xxxx”
(where x can be any number from 0000 through 3600). The Qualification log records
how many satellites were tracked over a given hour. If for every second of the hour a
tracked satellite was in view, the Quality value will equal 3600. For every second
VelaSync tracked less than the minimum number of satellites, the value will be less than
3600. The minimum requirement is one satellite at all times after the unit has com-
pleted the GNSS survey and indicates “Stationary”. A minimum of four satellites are
required in order for the GNSS survey to be initially completed.
If all entries in the qualification log are displayed as “0=3600”, a constant GNSS recep-
tion problem exists, so the cause of the reception issue is continuous. If the unit occa-
sionally shows 0=3600 but at other times shows that 1 through 12 have numbers of
other than “0000”, the reception is intermittent, so the cause of the reception issue is
intermittent. If the Quality value normally equals 3600 but drops to lower than 3600
about every 12 hours, the issue is likely caused by the GNSS antenna having an obstruc-
ted view of the sky.
E x a m p l e G P S Q u a l i f i c a t i o n L o g E n t r y :
6 = 151 7 = 1894 8 = 480 9 = 534 10 = 433 12 = 108 Q = 3600
In this example, VelaSync tracked no less that 6 satellites for the entire hour. Out of the
entire hour, it was tracking 6 satellites for a cumulative total of 151 seconds (not neces-
sarily in a row). For the duration of the hour, it was tracking, 7, 8, 9, 10 and 12 satellites
for a period of time. Because it was tracking at least at least one satellite for the entire
hour, this Quality value is Q=3600.
Note: If VelaSync is not connected to a GNSS antenna, this log will
remain empty.
System Log
Displays log entries related to the Timing System events and daemon events (such as
the Alarms, Monitor, Notification, or SNMP daemons starting or stopping, etc.)
Timing Log
Displays log entries related to Input reference state changes (for example, IRIG input is
not considered valid), antenna cable status. Examples include:
GR
GR = GNSS Reference
1
antenna fault : The GNSS Antenna Problem alarm
indicates the GNSS receiver has detected an over-current or undercurrent
1
GR = GNSS Reference
4.7 Quality Management
CHAPTER
4
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