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iGage
iG8 User Manual
Each of the other Base setup buttons requires that the
entered position be very close to the true antenna
position. SurvCE enforces a 5-second rule: the
programmed Phase Center position has to be within 5-
seconds of the True location of the receiver. In Salt Lake
City Utah:
5 seconds is around 500 feet of northing
5 seconds is around 385 feet of easting
If you exceed this tolerance, the following error message
will be displayed by SurvCE:
You should NEVER click Yes to continue. Always click No
and fix the problem.
If you configure the base with an errant position, your
rover will take a very long time to FIX and you will have a
horrible day in the field.
Double Check Your Base Position
When you use any method other than ‘Read GPS’ to set a
base, it is recommend that you follow the following
procedure to do a Read GPS so you can compare the
entered position to the receiver’s actual measured
position:
Configure the base up to the point where you are
prompted for a base position:
First click ‘Read From GPS’.
Do a 5-point average, then record the ‘Base
Configuration’ Lat/Long/EHeight results in your field
book:
If you don’t carry a field book, just take a picture of the
screen with your smartphone.
Now click on ‘No’ and SurvCE will return to the ‘From
New/Known Position’ screen and you can use the base
initialization method that you really want to use. After
you choose the desired position you will return back to
the Base Configuration screen again. Compare the
computed position to the measured position. They
should be very close:
In this example the Latitude and Longitude are both
within an arc-second. But the Ellipsoid Height is in error
by more than 152 feet from the averaged position. This
is an error!
If you continue setting the Base with this errant
position, the Rover will be extremely slow fixing. Your
rover will not report stable positions and your field day
will be miserable. The control point that you have
selected has the WRONG elevation. You need to fix it.
