[ntp:questions] Slow convergence of NTP with GPS/PPS

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Fri Oct 24 08:26:49 UTC 2008

>It isn't NTP which is the limit, but the GPS receiver acquiring lock from 
>scratch after an indeterminate period of being switched off.  The GPS 
>could take minutes to lock and declare that it has valid time.

>From the spec sheet for the Garmin GPS 18x:

  Reacquisition: Less than 2 seconds
  Hot:           Approx. 1 second (all data known)
  Warm:          Approx. 38 seconds (initial position, time, and
              almanac known; ephemeris unknown)
  Cold:          Approx. 45 seconds

I believe that's typical of modern GPS receivers.

These are my opinions, not necessarily my employer's.  I hate spam.

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