If you have having trouble with a feature, please
record a file (built into the program) and send it to me at
the email shown on this page so I can run the file and see
where the problem is. Otherwise, I will not be able to find
or fix it. Thanks.
Note: The preceding two links download .ZIP files.
If you do not have quality ZIP/UnZIP capabilities, please download an excellent FREE ZIP handler (and SO much more) named jZip from www.jZip.com.
(No, I don't get any money out of this recommendation. It is just a very good program I use a lot.)
Here is a graph showing the tracks of GPS and Glonass satellites over a couple of days.
In the preceding image, GPS satellites are tracked in blue and Glonass sats are tracked in red. GPS (USA) PRNs are 32 and less. Glonass (Russia) PRNs start at 64 and go up. The center of the plot is in Vallejo, CA, near the cities of San Francisco and Napa near 38° 08'N / 122° 12'W. I can almost see "over the top" from here but not quite.
You can see a couple of interesting things from this plot
from the free NMEAgent program. GPS sats have a lower
inclination than do Glonass sats. That means that
Glonass sats go closer to the north and south poles than do
GPS sats. GPS sats do not hit the same track every
time. It is general "knowledge" that GPS sats are in the
same place in the sky every day, twice a day. While that
is somewhat true, they precess across the sky and the orbit
time is about 4 minutes short of making it to the same place
every day. But Glonass sats, while about 45 minutes
short of a repeating orbit, hit orbits which precess across
the sky in about an 8 day repeating cycle. You can see
the rather regular pattern of the red traces around the
pole. These tracks were recorded across a couple of days
by NMEAgent software. The numbers on the chart are PRN
numbers. Since Glonass sats don't have well associated
PRN numbers, these are the ones assigned as of the date this
track was recorded - Sep. 2, 2014.
These days, there are many GNSS receivers that are without
a display. This makes them cheaper. They can be
plugged into various devices and those devices become the
display for the GNSS receivers. Google Earth will accept
NMEA input from a GNSS receiver connected to a compatible
device speaking NMEA data. That is how this display was
developed. The track was partially developed using a
GT-321R and partially from a Holux M-215+. The Holux
sees only one WAAS sat but will not track it. The
GT-321R will track either GPS+WAAS or Glonass. So a
complete picture can be developed but it needs input from
both. I am hoping to find a receiver that will display
GPS+WAAS+Glonass. There is supposed to be a uBlox based
unit which will do this as of their release 8. As of
now, these units are not widely available. I will try to
get one when they do become more generally available.
PyGPS - Python GPS
Reader (Almost complete
now. Just a few tiny things to fix up.)
See/Get the source code
Here is the main screen with information about the
GPS sats and where you are. I wrote this to try to
learn Python. I wanted a full screen product running
on Raspberry Pi. This is it (for now). It is not
the best language I have ever learned but it is adequate
as long as you have access to the web for help and answers
to questions. I took a course from LinkedIn and bought
the very good intro book by Simon Monk. Those two
learning platforms and lots of years of programming got me
started. This is the product of about 3 weeks of
learning everything just before I did it. It is a
rewrite, and in some respects better, than the VB version I
did many years ago (see above). This is only for a
Linux platform for now. Maybe that will change in the
future. Or not...
And now some
space music. This is an album of music from the Space
Oddesy Orchestra and Choir.
You have never heard of them. This is the only album so far. Give them a listen.
Cut 01-Space Oddesy Choir-Floating Over Saturn
Cut 02-Space Oddesy Choir-Delving into Saturn
Cut 03-Space Oddesy Orchestra-Duet at the Core of Saturn
Cut 04-Space Oddesy Orchestra-Christmas on Mars
Cut 05-Space Oddesy Mens Chorus-Breakfast on Venus
Cut 06-Space Oddesy Choir-It's So Hot on Mercury
Cut 07-Space Oddesy Orchestra-Traveling to the Outer Reaches
Cut 08-Space Oddesy Orchestra-And We're Gone