Hey Bob,

Try atomic clocks, they are precise and independent of gps.

YT


On Sat, Apr 20, 2013 at 1:11 AM, Bob Axtell <engineer@cotse.net> wrote:

> My need is precision time, nothing else. Before GPS, ships navigated
> knowing the time
> and the sun angle. I know where I am at, so with a precise clock, I can
> obtain the sun angle.
>
> It seems to me that there would be little reason to shut the time
> service off, which only needsONE
> bird.
>
> --Bob A
>
> On 4/19/2013 7:27 AM, RussellMc wrote:
> >> This came up in a conversation related to solar tracking. Will the
> >> military shut off
> >> ALL of the GPS services, or just positioning, during a wartime footing=
?
> >>
> >> How about time/date services?
> > First casualty is to change to "selective availability"
> > Accuracy drops substantially.
> > This was the mode the system ran in fr many years when first introduced=
..
> > AFAIR this was done for 'Desert Storm'.
> >
> > I do not know if it is done, but you could shut it down regionally so
> > that a portion of the globe was without service. How small and well
> > defined you could do this would be "interesting".
> > A very determined person could gain useful information from two
> > satellites and possibly from one.
> >
> > Russia operates a GPS system (GLONASS*) that (memory says) uses polar
> > elliptical orbit satellites as in that orbit shape they are in the
> > high poleward part of their orbit for the  majority of the time.
> > Usefulness diminishes as you go southward. If they transmit around the
> > whole orbit you MAY get some use from low altitude satellites in the
> > southern hemisphere.
> >
> >
> >
> >            Russia
> >
> > ___________________
> >
> > http://en.wikipedia.org/wiki/Satellite_navigation
> >
> > http://en.wikipedia.org/wiki/Global_Positioning_System
> >
> > Says:
> >
> >             Initially, the highest quality signal was reserved for
> > military use, and the signal available for civilian use was
> > intentionally degraded (Selective Availability). This changed with
> > President Bill Clinton ordering Selective Availability to be turned
> > off at midnight May 1, 2000, improving the precision of civilian GPS
> > from 100 meters (330 ft) to 20 meters (66 ft). The executive order
> > signed in 1996 to turn off Selective Availability in 2000 was proposed
> > by the U.S. Secretary of Defense, William Perry, because of the
> > widespread growth of differential GPS services to improve civilian
> > accuracy and eliminate the U.S. military advantage. Moreover, the U.S.
> > military was actively developing technologies to deny GPS service to
> > potential adversaries on a regional basis.[18]
> >
> > __________________
> >
> > GLONASS
> >
> > http://en.wikipedia.org/wiki/GLONASS
> >
> >           iPhone 4S, iPad Mini and HTC provide GPS & GLONASS capability=
..
> >
> >           GPS and phone baseband chips from  ST-Ericsson, Broadcom and
> > Qualcomm support GLONASS in combination with GPS.
>
>
> --
>
> The only place success comes before work is in the dictionary.
>
> VINCE LOMBARDI
>
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