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

Richard B. Gilbert rgilbert88 at comcast.net
Tue Aug 30 22:30:25 UTC 2011

On 8/30/2011 12:05 AM, NPG wrote:
> On 8/29/2011 9:59 PM, Chris Albertson wrote:
>> The other source of time is CDMA.   This is a signal sent from cell towers.
>>   This can be better then WWV/WWVB.     There are many CDMA based NTP
>> servers.  Some pool servrs are CDMA but I bet you will not find any WWV
>> based servers
> OK, I'm learning how not to do it. and a few ideas on how to do it.
> It sounds like the WWV or WWVB signals are not desirable for accurate
> timekeeping.

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.

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