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My question/problem is once my set up is complete and I go and tell the controller to start survey, Iget 100%reliability my sats drop in half meaning i have say 12 to 13 it goes to 6or7 . the glonss box and lc2 are both checked

Bri in fl

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  • Did you check and see which birds are being dropped?

  • Land Surveyor

    We use Topcon Hiper+, and we've also seen some issues with the same number of sats available versus able to use.  We thought it was a radio problem initially, but we've seen it on other units as well.

    glonass have been the usual suspects that show up but aren't active.

  • Check the firmware and settings on radio. Another possibility (after Darren's) is that you're not transmitting all the data. I'm speaking from experience that the wrong firmware or settings can keep you from broadcasting the GLONASS part of the signal. A way to know if this is the specific issue is to look at 'which' satellites are being dropped. Contact your local re-seller to help you check the current firmware on ALL pieces in the puzzle and the typical settings for your scenario.


  • Land Surveyor

    Hi Brian,

    How many sats is your base picking up? It may sound obvious to some, but if you are new to the technology it may not be. Your Rover will only be able to sync with the same sattelites that your base is getting, so if your base is not in a prominent position you may be blocking some of them out... I have some other ideas, but by process of elimination, this comes to mind first..

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