[ntp:questions] NTP Performance on WINNT

David J Taylor david-taylor at blueyonder.not-this-part.nor-this.co.uk.invalid
Mon Jul 20 16:55:22 UTC 2009

Richard B. Gilbert wrote:
> That is what a "site survey" is.  The GPS determines its location a
> few hundreds of times over the course of a day and does a "least
> squares" calculation to get a reasonable approximation of your
> latitude and longitude.
> Cellular phone base stations do a more extended site survey, thirty
> days instead of one.  This gives them a MORE reasonable
> approximation.  When I did my site survey (24 hours) the locations 
> plotted a locus about
> 300 feet long in an East-West direction and with a width of about
> thirty feet.
> If I had had the patience and if I had required sub microsecond
> accuracy I could probably have trimmed that locus further.  . . . .
> It is enough, for me, that my little herd of computers agree as to
> approximately what time it is.

Thanks, Richard.  I took your "You do need to run a "site survey"" as 
something rather more involved than letting your GPS just sit there.

For me, a few milliseconds is good enough, but I always want to do 


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