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GSM19 Series Magnetometers - Version 7
GEM Systems, Inc. Advanced Magnetometers
For more technical information, visit www.gemsys.ca
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Rotated Grid. Grid rotated through a specific angle as defined by the first two waypoints on the
starting line.
If you turn GPS off, you only have standard X-Y and LINE / STATION formats available to you.
The X-Y system uses a Cartesian coordinate system whereas LINE / STATION uses line and
station numbers that are both annotated with directional information (ex. N, S, E, W and more).
Both systems are valid; the X-Y system may be somewhat easier to deal with as numbers do not
require later manipulation; LINE-STATION positions are annotated as described above and may
require that you remove the annotations later in the post-processing stage (which requires more
work).
This section describes how to use the Automatic Grid waypoint option with the UTM positioning
option.
5.
Select the position option. You have four options available, including UTM, Lat / Long,
Local Grid and Rotated Grid.
6.
Select C-change. The system displays the select positioning system screen. Use C-change to
toggle to the positioning option that you want to use. In this case, select UTM.
7.
Press F-ok. The system displays the select picket marking screen. This is the screen enables
you to annotate UTM values in the magnetometer’s output file at designated locations.
What happens with Walking mode is that you can mark pickets at designated stations (i.e.
UTM values are added to the file when you press F during the survey). For example, if you
are walking along the grid and reach a picket that you want to identify with specific UTM
locations, you would then press F at the picket location. These values are added to the file.
8.
If you want to change the marking system, press C. The system shows the next possible
option. For now, choose the XY option and press F-ok when finished. The system displays
the X-Y detailed positioning screen.
9.
Start by setting the position. Here, we use x=0, y=0 as the start of our grid; you can use any
values that are appropriate for your project.
10.
The increment value controls the data acquisiton locations
along the line
. If your plan for
the survey grid is to run vertical lines at 1m spacings, move the cursor to the increment
values, select C-clear and then E-enter until increments are set to set x=0, y=1. When
finished, select E-Enter. Alternately, iIf your plan is to run horizontal lines, set x=1, y=0, for
instance, for the increment.
11.
The EOL increment controls the
line spacing
. For example, if you are using vertical lines
and lines spaced at 2m, set x=2, y=0. Or, if you are using horizontal lines spaced at 3m, set
x=0, y=3.