[time-nuts] TruePosition GPSDO Holdover Issues
Chase Turner
ke4qdl at gmail.com
Tue May 15 21:32:08 UTC 2018
On Tue, May 15, 2018 at 3:27 PM, Hal Murray <hmurray at megapathdsl.net> wrote:
>
> If you are far enough north, you are in the hole, but you can see the
> other
> side of the hole over the pole.
>
> It's not hard to make your own plots. This is from 66 38' north.
> http://users.megapathdsl.net/~hmurray/time-nuts/Arctic/Polar-A.png
>
> If anybody wants to play, I'll put the code on the web.
>
> There are several steps. First is to collect the data. I have a python
> script that grabs everything from a NMEA device and logs each line with a
> time stamp. The GPS orbit period is 12 hours so you need 12 hours of data
> to
> see everything. But there are 30 satellites, so a few hours will show the
> hole.
>
> The next step is to extract the data into a useful format. That's another
> python script. Then, just feed that to gunplot.
>
Hi Hal,
I'd like to see a copy of the code, please.
Thanks!
--
Chase Turner
W4TI
http://w4ti.com
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