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The following plot is for the old 25-HVS model for 3 days prior to the swap:
The NTPClockOffset ranges from approximately 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 jumps in GPSdiff_max events seem to happen when the number of tracked satellites changes, indicating 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 PPS signal is effected by these events.
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