anyone running GPS clocks in Southeastern Georgia?

Joel Jaeggli joelja at
Fri Jan 21 16:49:44 CST 2011

On 1/21/11 2:26 PM, Robert E. Seastrom wrote:
> Michael Holstein <michael.holstein at> writes:
>>> I'd be curious to see what effects (if any) those who use
>>> GPS-disciplined NTP references in Southeastern Georgia see from this
>>> experiment.
>> Aren't CDMA BTS clocked off GPS?
>> NTP isn't going to be the only "ripple".
> Sure, and there are GPS-steered Rb clocks in telco-land too as well as
> a ton of stuff I don't know about yet until everyone else here chimes
> in; it's just that NTP is highly visible to NANOGers.

if your high quality stratum one time source isn't capable of
free-running for a little while then it's not really high quality...

you can of course test this simply by disconnecting the antenna. if the
dilution of precision gets sufficiently high or the boise floor climbs
above the signal then it should fail the gps out of the mix. our
symerticoms have upgraded ocxo and backup geographically distant ntp
sources in the pool to account for localized gps failure...

I'm way to cheap to spring for the rubidum upgrade, the ocxo holdover is
supposed to be 1ms a day.

> -r

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