[ntp:questions] NTP Performance on WINNT
David J Taylor
david-taylor at blueyonder.not-this-part.nor-this.co.uk.invalid
Mon Jul 20 16:06:42 UTC 2009
Richard B. Gilbert wrote:
> Assuming a GPS *TIMING* receiver, and that it can be installed with
> the antenna having a good view of MOST of the sky, you can expect
> results that are *almost* as good as the atomic clocks on board the
> You do need to run a "site survey" to establish your location as
> exactly as possible! Once your location is known, the calculation of
> the "speed of light delay from your selected satellite to you can be
> done quickly and easily.
I didn't have such difficulties when using today's sensitive GPS devices -
e.g. GPS 18x LVC:
Having a view of, say, a 180-degree arc of southern sky is probably good
enough. I have mine indoors, sitting on top of a PC on the top floor of
my building. No separate antenna. The earlier GPS 18 LVC sits on the
roof. The GPS determines its location all by itself - no site survey
required. Microsecond accuracy.
Of course, if you are looking at a basement located or tempest-spec server
room, using GPS becomes rather more difficult!
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