VeEX TX300s, Руководство пользователя

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Discipline Source Phase Measurement
11. Close the Phase Graph and verify that the Disciplining Status gets into Locked mode.
At this point the test set’s internal “Atomic 10MHz” frequency and “Atomic 1PPS” timing reference signals can be considered
accurate and stable.
The Phase Graph (above) can be used to monitor the short-term stability of the raw GPS clock, which can be used to determine the
Discipline Threshold for a particular site or scenario. Zoom in to the 50ns grid and estimate how dispersed the 1PPS samples are (in
ns), then use a larger value as a threshold. A vertical variation of <30ns is OK.
Clock Disciplining - Using External 1PPS from a PRTC (Cs or Rb)
The TX300s can also be disciplined, faster and more accurately, using a 1PPS reference signal from a traceable time standard
(PRTC), which can be connected to the test set’s ToD port (RS232).
An RJ11-to-BNC cable is required (RJ11 pin 2 to the BNC’s center pin and RJ11 pin 4 to BNC shield/GND). Keep in mind that the
same RJ11 form factor comes in 4 and 6-pin versions and this document refers to the 6-pin version.
RJ11 to BNC
TX300s_Platform_Manual_RevB00 Page 94 of 104