[ntp:questions] refclock on Windows graphs

David J Taylor david-taylor at blueyonder.neither-this-bit.nor-this.co.uk
Tue Mar 17 17:25:02 UTC 2009

Dave Hart wrote:
> Unusually for me, the configuration and code on my reference clock
> test machine has been static for the last two days UTC.  I've posted
> loopstats and graphs for that period on http;//davehart.net/ntp/
> refclock/
> Cheers,
> Dave Hart

The program which Dave used to produce his graphs from loopstats data is 
available in an unsupported beta version here:


I'm running Dave's updates to ntpd.exe, with his serial PPS driver on an 
old 1.9GHz Pentium 4 PC, and seeing average jitter values around 2.3 
microseconds (when fed from a 1 microsecond GPS).  The offsets are still 
more than I would like, being typically from -100 to +200 microseconds, as 
temperature varies throughout the day, producing almost 3ppm peak-to-peak 
frequency variation.


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