VeEX VePAL TX320s, Руководство пользователя

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Relative phase compares disciplined Atomic 1PPS vs. GPS 1PPS
Relative phase measurements are more useful when monitored at the beginning of the disciplining process, to track the phase
alignment between the oscillator’s output (Atomic 1PPS) and its input (GPS 1PPS). Since the oscillator filters the raw 1PPS noise
and fine tunes its frequency to align its own 1PPS to true time, the input vs output differential graph can become a very useful tool to
monitor and verify that the convergence process is going as expected.
The Atomic Phase Graph can be found in the Atomic Clock settings and status screen at >Utilities >Settings >More
>High Precision Clock Source >Atomic Clock
Example of GPS-disciplined Atomic relative phase convergence graph
Yellow dots indicate valid relative phase measurements (output - input).
Scattered yellow dots could indicate bad GPS signal, which in turn provides bad timing accuracy, or that the oscillator trying
to compensate for large phase differences.
White dots (line) at zero indicates loss of GPS 1PPS. It basically indicates holdover periods.
What you want to see in this graph is a tight bundle of differential phase measurements forming a line converging to zero and
staying at zero. Since the Atomic Clock output is very stable, it will slowly try to infer the true (accurate) time alignment out of the
GPS 1PPS output and maintain it. The less disperse the individual measurements (dots) are, the better the GPS timing signal is. So,
you want to see a straight line formed by not-so dispersed group of dots.
Example of proper (converged and stable) phase alignment
TX300s_Platform_Manual_RevB01 Page 46 of 123