[ntp:questions] NTP architecture recommendation

Uwe Klein uwe_klein_habertwedt at t-online.de
Sun Aug 19 21:48:35 UTC 2007

David J Taylor wrote:
> Richard B. Gilbert wrote:
> []
>>I don't think that a 14 channel receiver would be useful!  There
>>simply are not that many satellites!  The last I knew, there were 27
>>NavStar (GPS) satellites in orbit.  Of these, about seven are usually
>>above the horizon at any one time.

The Sirf Chipset forex supports 20 receiver chanels
( Regular GPS Sats and Egnos Signals )
With bi or trilingual Receivers you may see even more sources.
> Richard,
> There can be more than that - here's an example with 13 visible.
>   http://www.david-taylor.myby.co.uk/software/wxtrack-extras.htm
> According to this source, there are 31 active satellites:
>   http://celestrak.com/NORAD/elements/gps-ops.txt
> More in orbit, I expect, now dead.
> What do they do with decommissioned GPS satellites?

afair they get a push into an orbit a bit outside the system "shell".
20000km is a bit high for deorbit. low flying sats are sceduled for

> Cheers,
> David 


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