[ntp:questions] dcf77 time synchronization problem

Ulrich Windl Ulrich.Windl at RZ.Uni-Regensburg.DE
Fri Aug 13 11:20:54 UTC 2010

<Wolfgang.Hennerbichler at ooe.gv.at> writes:

> Hi ntpd folk, 
> This will be a long email, I hope somebody is able to help. In short: My
> dcf77 doesn't work very well and I don't know exactly why. 


A few basics:

Whenever DCF-77 receives a bad spike, it needs at least
120 - "time of the spike" to synchronize again. Maybe even one extra
minute to be sure.

The DCF-77 antenna is directional, so you need to have it turned in the
right direction. Unfortnuately it's not easy to find the optimal

For the clock hopping: Use "ntpq -p" to find out whether your DCF-77 has
a significant offset against the other servers. You'll ahve to minimize

I'd suggest to capture long-term statistics of the clock status. With
the parse driver "ntpq -c cl" should display the statistics.


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