[ntp:questions] Raspberry Pi error in PPM offset

David Taylor david-taylor at blueyonder.co.uk.invalid
Fri Aug 23 03:45:38 UTC 2013

On 23/08/2013 03:27, JP wrote:
> I have access to an accurate frequency counter that I use to measure the Pi's actual crystal frequency. I find that the PPM error reported by NTP differs from the real PPM error consistently by about 2.5 PPM. i.e. when measured over a time period of several days, the difference between the actual PPM error and the reported PPM error varies slightly above and slightly below 2.5 PPM.
> I'm suspecting that there is a configuration issue in the RPi kernel, but, being new to NTP, I'm not sure where to begin looking. Any suggestions?
> Thanks,
> James

James, is the average PPM about right?  I'm not sure you can expect more 
than that.
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