[time-nuts] DCF77/PZF correlation after outage

Martin Burnicki martin.burnicki at burnicki.net
Wed Apr 23 08:04:21 UTC 2014


Ben Stienstra wrote:
>> Thanks for your reply. The correlation coefficient is almost back at
>> the normal level. I will search some old logs to see if previous
>> outages also shows the same behaviour. It could be perfectly normal.
> Martin, I have combined all the data i have from the previous firmware
> version (v5) and the current (v6). At other outages the correlation
> coefficient did come up to >95% almost as fast as the field strength
> (not days). The last reboot log shows 10 minutes until 'NTP sync to PZF'.
> DCF Outage 2014-01-25:
> http://imgur.com/xinzUGL
> DCF Outage 2013-06-20:
> http://imgur.com/QMYEOkR
> In the image below you'll find the field strength and correlation over
> the past 10 months. Field strength in the summer was higher than in the
> winter. The low corr. at the beginning of the graph was when the antenna
> was not yet outside and aligned.
> http://imgur.com/sZnfSxz

I'd also expect that the correlation comes back quickly after an outage.

Although I've been involved in the development of the first DCF77 
correlation receivers many years ago the firmware of these receivers is 
actually maintained by other guys, one of which is still on Easter holidays.

I've forwarded your observations to the firmware maintainers, so they 
can try to find out what happened. However, this may take some days.

> I'll continue monitoring and when the next outage occurs, let's see what
> happens. I'll contact support instead of the time-nuts list :)

Great. Usually Meinberg support is pretty responsive.

Take care, I'm biased. ;-)

Martin Burnicki

Senior Software Engineer

MEINBERG Funkuhren GmbH & Co. KG
Email: martin.burnicki at meinberg.de
Phone: +49 (0)5281 9309-14
Fax: +49 (0)5281 9309-30

Lange Wand 9, 31812 Bad Pyrmont, Germany
Amtsgericht Hannover 17HRA 100322
Geschäftsführer/Managing Directors: Günter Meinberg, Werner Meinberg, 
Andre Hartmann, Heiko Gerstung
Web: http://www.meinberg.de

More information about the Time-nuts_lists.febo.com mailing list