[ntp:questions] Two time sources with offset => fails to synchronize

Richard B. Gilbert rgilbert88 at comcast.net
Tue Feb 12 17:10:19 UTC 2008

Serge Bets wrote:
> Hello Thierry,
>  On Tuesday, February 12, 2008 at 10:39:21 +0100, Thierry MARTIN wrote:
>>It seems that the Radio clock has 50ms offset compared to the GPS
>>source, which leads a failure in synchronisation.
> Radio clocks may need a fudge factor, typically around 20 ms, to report
> the right time. That's due mostly to filter delays in the radio
 > Anyway even if all else gets
> perfect, you still have the worst number of clocks problem. One is good;
> two worst; four best.

Four is not necessarily "best".  It's the smallest "robust" 
configuration.  Five and seven are the next two magic numbers in that 

One is not necessarily good or bad; the problem is, if it's bad, how do 
you know?

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