[time-nuts] Features of a Precision Clock - Grid

Tim Shoppa shoppa at trailing-edge.com
Sat Oct 7 16:47:55 EDT 2006

> Does anybody have a URL for the frequency specs?  (US or California.)

Already people have said there are no guarantees, but my experience:

instantaneous frequency might go up and down one or two tenths
of a percent for periods of time of minutes to tens of minutes and
sometimes (but not often) hours.

Over a whole day, they seem to try to average it out and it was rare
(over my measurements) for a 60Hz wallclock to lose or gain more than a few
seconds a day.

My frequency measurements were done with a long-period frequency
counters, crystal timebase good to a few ppm, and time measurements
was comparing the wall clock to WWV. In other words, not very high-tech
by the measurement standards of many here!


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