What are the fields in the DIFFERENTIAL SETUP screen for?
A description of the fields follows: Elevation Mask: PC-GPS will not use satellites below this angle (degrees above the horizon). This number should be the same as the elevation mask of the base station. If you are not sure, enter “0”°. Alt. Control: Set this to “No altitude control” most of the time. The other options apply only when you are getting poor reception. The other options give you a way to correct 2D points if you know your altitude. If you know the altitude of the job (assuming all points in the job are at about the same altitude) you choose “altitude always fixed.” All points will then be fixed to the HAE altitude in “Enter Altitude for above (if needed).” • Example: You collect points on the streets of a city. You get poor reception (because of the buildings, for example.) Most of your points are 2D, so they can not be differentially corrected by normal means. However, you know that the elevation was about 250 meters HAE, so you set ALT Always fixed to 250. All points in
