Explorer with GPS - 'No Fix'

CraigTowell

Hi,

I'm using explorer desktop with a trimble dGPS unit for positioning.   When I activate the GPS I get the red warning triangle symbol, but when I move around the symbol moves around with me (accurately) so I think I do have a good GPS lock.... why do I not get the green dot instead of the red triangle?  Also, when I check in the GPS tab of the options, it tells me I have 11 satellites in view, 9 in use but no fix.

I'm pretty sure I have the settings correct (NMEA, baud rate etc...) as I've checked on the GPS reciever to see what it's outputting.

Any help greatly appreciated!

Craig

norie

Hi,

I'm using explorer desktop with a trimble dGPS unit for positioning.   When I activate the GPS I get the red warning triangle symbol, but when I move around the symbol moves around with me (accurately) so I think I do have a good GPS lock.... why do I not get the green dot instead of the red triangle?  Also, when I check in the GPS tab of the options, it tells me I have 11 satellites in view, 9 in use but no fix.

I'm pretty sure I have the settings correct (NMEA, baud rate etc...) as I've checked on the GPS reciever to see what it's outputting.

Any help greatly appreciated!

Craig

I believe AGX uses the $GPGSA sentence to determine the signal strength indicator. Specifically, the 3D-fix status:

• 1 - No Fix
• 2 - 2D Fix
• 3 - 3D Fix

I've had the same issues. I believe AGX basically ignores the DOP values and satellite connection information when determining signal strength/accuracy.