[time-nuts] GPS position averaging software?

[Mark Sims]

Why Lady Heather, of course!  Requires a Thunderbolt.  

Use the S)urvey P)recision command.  You can specify the number of hours to run for (default is 48).   During the survey all the fixes are written to the file LLA.LLA  and plotted on the screen (each hour in a different color).  It does some pseudo sophisto statisto mumbo jumbo on the fixes and comes up with a pretty good guess where you are and saves that as your location.   You can also read in a .LLA file and it will plot the fixes,  or you can process them with your own software.  You can stop a survey early if you want (I don't rememeber if it saves the position if you do that)

I have tested lots of different antennas and the differences can be rather significant.  My best survey grade choke ring comes in within less than a foot.   Crappy patch antennas can be off over 10 feet.

If you just have to use the M12 receiver,  you could format the fixes into a .LLA file and then read it with Lady Heather.  You can start the program with the /0 option to disable its attempt to use a serial port to talk to a thunderbolt.  Also note that the program does not buffer the fixes... if you redraw the screen, etc,  the plot goes away.  And you can't zoom the LLA plot to full screen.


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Just got a pair of GPS antennas on the roof and I'm interested in both 
getting as accurate a position survey as I can, and in comparing the 
performance of the two antennas -- one is a choke ring, the other a 
Motorola Timing2000.