[ntp:questions] Questions about joining pool.ntp.org

Chris Albertson albertson.chris at gmail.com
Tue Aug 30 23:05:18 UTC 2011

> If you care about microseconds or nanoseconds, shortwave radio is a poor
> choice.  The length of the radio propagation path changes constantly! Not by
> much but if you care about the nanoseconds. . . .
> If you REALLY NEED the nanoseconds, buy an atomic clock and have it
> calibrated by your national standards people.  If you don't REALLY NEED
> the nanoseconds you can almost certainly save $50K - $100K.

GPS, eBay and the cell phone industry have changed that.   Prices have
fallen to well below $1K  or even below $100 if you can do some soldering.
 For example Synergy's "12MT+" receiver has a 2 nanosecond (1 sigma) error
and sells for $60 new.   It is easy to find a good working Rubidium
oscillator (a kind of "atomic clock") on eBay for $100 to $150.

Chris Albertson
Redondo Beach, California

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