Spectracom NetClock 9400 Series, Руководство пользователя

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Reported TFOM Value Estimated Time Error (ETE)
11 1 sec < ETE <= 10 sec
12 10 sec < ETE <= 100 sec
13 100 sec < ETE <= 1000 sec
14 1000 sec < ETE <= 10000 sec
15 ETE > 10000 sec
Example
TFOM is a value between 1 and 15. TFOM can never exceed the default MaxTFOM value of
15.
Typically the MaxTFOM requires no adjustment, but in some instances it may be advisable to
decrease MaxTFOM so that TFOM can potentially exceed it: For example, by lowering the
MaxTFOM to “5” it is now possible for TFOM to be always higher than the MaxTFOM value:
Assuming the MaxTFOM is set to 5 and the TFOM happens to go to a 6, i.e. TFOM is now
exceeding MaxTFOM. This condition will cause a 1PPS out of specification alarm to be asser
ted and the
oscillator disciplining will change
in order to speed-up the alignment of the sys
tem 1PPS to the selected reference (causing it to take less time getting closer into alignment with
the reference):
This will cause the TFOM to start to decrease faster. Once TFOM no longer exceeds MaxTFOM
because the
System 1PPS is now much closer to the reference 1PPS , the disciplining slows back
down again as the system 1PPS continues to be brought into alignment with the selected 1PPS
input.
3.5.3 Monitoring the Oscillator
The Oscillator Management screen provides current and history status information on dis
ciplining state and accuracy.
To access the Oscillator Management screen:
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CHAPTER
3
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NetClock User Reference Guide Rev. 16
3.5 Managing the Oscillator