Spectracom 8183A GTP, Инструкция по эксплуатации

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Section 3: Operation
NetClock/GTP Instruction Manual Page 3-3
The lamp remains green if the receiver continues to track, or has tracked, at least
one qualified satellite within the period allotted for the GPS Lock Alarm. The
default period is set for 15 minutes. The GPS Lock Alarm period can be
configured up to 24 hours using the
LOCK command. Refer to Section 4 for a
complete description of the LOCK command.
The lamp turns red when the receiver is unable to track any satellites and the
GPS Lock period has expired. At this point a GPS Lock Alarm message is output
on the Serial Setup port.
After the receiver reacquires at least one qualified satellite for one minute, the
GPS Lock lamp turns green. Another status message is sent to the Serial Setup
port that the GPS Lock Alarm has been cleared.
Refer to Section 3.2.8 for additional information on the GPS Lock Alarm.
3.1.3 Time Sync Lamp
This bi-color LED indicates the time synchronization status to GPS. At power on
this lamp is red, indicating that the clock is not synchronized and time data
accuracy does not meet specification.
The lamp turns green when the receiver has acquired at least one satellite and
has recovered the GPS system almanac. The entire GPS system almanac takes
12.5 minutes to transmit. The time data accuracy shall now conform to
specifications. The lamp remains green if the receiver continues to track, or has
tracked, at least one qualified satellite within the period allotted for the Time Sync
Alarm. The default period is two hours. The duration of the Time Sync Alarm
period is dependent on the accuracy requirement of the application. The Time
Sync Alarm period can be configured up to 24 hours using the
SYNC command.
Refer to Section 4 for a complete description of the SYNC command.
The lamp turns red when the receiver is unable to track any satellites and the
Time Sync Alarm period has expired. At this point, a Time Sync Alarm message
is output on the Serial Setup port to warn that time data accuracy may be
compromised.
The lamp returns to green only upon acquiring and qualifying at least one
satellite for 1 minute if the almanac data is still valid. If the almanac is invalid or
lost due to a power failure, the clock will have to again recover the complete
almanac (12.5 minutes). When the receiver reacquires Time Sync, a status
message is sent to the Serial Setup port that the Time Sync Alarm has been
cleared and timing accuracy shall meet specification. Refer to Section 3.2.8 for
additional information on the Time Sync Alarm.