ntpsec is ignoring PPS
folkert at vanheusden.com
Tue Nov 30 21:25:00 UTC 2021
> > ntpq shows:
> > root at gpsdomonitor:~# ntpq -c pe -n
> > remote refid st t when poll reach delay offset
> > jitter
> > oPPS(0) .PPS. 0 l 12 16 377 0.0000 -0.0114 0.0040
> > xPPS(1) .PPS. 0 l 1 2 377 0.0000 490.4861 0.0065
> > nl.pool.ntp.org .POOL. 16 p - 64 0 0.0000 0.0000 0.0019
> What are the units of offset? Is it just that PPS1 is offset so much it
These are milliseconds.
> is flagged as a bad clock? Especially if it is considered a stratum 0
> clock it should not be that far off.
Not sure. But as Gary suggested, I'll let it sit for a while to see if
> > PPS(0) is a regular garmin lvc18, while PPS(1) is a GPS disciplined
> > osc...that is divided to 1PPS using a "picdiv"
> Are you using PD11 and synchronizing to a known good PPS to get the output
> synchronized to true top-of-second? If you just divide 10MHz down to 1Hz
> you will get some random offset up to +/-500ms from the true top of
That's a very good point!
I am using a PD10 currently so yes that explains that offset. Thanks for
pointing me at that.
I'll see if I can flash a PD11 myself (sofar my aliexpress burner fails
to do so) or buy one from Tom van Baak.
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