[ntp:questions] First attempt GPSD/PPS ->NTP time server

David J Taylor david-taylor at blueyonder.neither-this-bit.nor-this-bit.co.uk
Fri Jan 25 08:20:23 UTC 2008

Dennis Hilberg, Jr. wrote:
> The GPS time is not very accurate anyway, and can vary wildly,
> probably depending on the device, so don't expect perfect offsets. On my 
> Garmin GPS 18 LVC, I use 0.190 which gets it in the ballpark,
> but can randomly jump +16ms to -10ms at any time.

With a good view of the sky, the GPS time should be within a microsecond. 
The fact that you have a 0.2s offset suggests you are synching to the 
trailing edge of the PPS signal and not the leading edge.  Is that 
possible?  Have you checked the polarity, and the flag2 setting?


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