[AMRadio] Strange, did aliens arrive?


ww2bom at sbcglobal.net ww2bom at sbcglobal.net
Fri Feb 24 21:54:25 EST 2017


GPS uses as I recall, Cesium standards that can reach stabilities of ≤1.0E-14 after 30 days. Ground stations monitor and track the GPS timing, and can adjust it. In general terms, Cell phone tower sites typically use Rubidium standards that are GPS disciplined and can reach stabilities of <2.5E-12 for site synchronization and timing, which is what your cell phone clock is locked to. I think WWV uses Cesium standards, but I can't say for sure on that with all certainty. 
Jim T.WB8HMD 

    On Friday, February 24, 2017 11:38 AM, Donald Chester <k4kyv at charter.net> wrote:
 

 > Speaking of Cell phone time, that is GPS locked. What does GPS use for a
> standard? If the GPS system is WWV locked, that might explain why I ended
> up in Seattle instead of Ft. 
> Bill,
> KB3DKS

The GPS carrier signals originate from on-board atomic clocks monitored by ground control stations.
Should be a lot more precise than WWV.

https://ilrs.cddis.eosdis.nasa.gov/docs/timing/gpsrole.pdf


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

______________________________________________________________
Our Main Website: http://www.amfone.net
AMRadio mailing list
Archives: http://mailman.qth.net/pipermail/amradio/
List Rules (must read!): http://w5ami.net/amradiofaq.html
List Home: http://mailman.qth.net/mailman/listinfo/amradio
Post: AMRadio at mailman.qth.net
To unsubscribe, send an email to amradio-request at mailman.qth.net with
the word unsubscribe in the message body.

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to ww2bom at sbcglobal.net


   


More information about the AMRadio mailing list

This page last updated 17 Nov 2017.