[ntp:questions] using both a PPS source and a HBG (dcf-77-like) timesource?

Dennis Hilberg, Jr. timekeeper at dennishilberg.com.invalid
Mon Jan 14 17:19:11 UTC 2008


Folkert van Heusden wrote:

<snip>
> Well if I remember correctly someone said to me once that the
> time-string returned by cheap gps device (like my garmin 18 lvc)
> sometimes is a bit off while its PPS signal is fine.
> 
> Currently I'm syncing against NMEA/PPS and seeing quiet a big offset:
> 
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
> xGPS_NMEA(0)     .GPS.            0 l    7   16  377    0.000  -185.08   1.001  <---
<snip>

You can even out that delay in the GPS time by using the 'fudge' option. 
Example:

server 127.127.20.0 minpoll 4
fudge  127.127.20.0 time1 0.185

I do the same thing with my GPS 18 LVC, only I use gpsd with the SHM drivers.

Dennis

> Folkert van Heusden

-- 
Dennis Hilberg, Jr.     \  timekeeper(at)dennishilberg(dot)com
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