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The NTPClockOffset shows spikes between -100000 to 50000 microseconds during this period, which is much worse than expected for a GPS/NTP reference clock. The spikes in NTPClockOffset are simultaneous with positive jumps in GPSdiff_max, up to as much as 2.5 seconds. These events seem to happen when the number of tracked satellites changes, which indicates that internal processing lags in the 25-HVS cause it to report late, causing large values of GPSdiff. It is unknown if The extent of this effect on the timing of the PPS signal is effected by these eventsunknown.
The following plot shows a close up of one of the clock offset spikes using un-averaged data:
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