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GSM19 Series Magnetometers - Version 7
GEM Systems, Inc. Advanced Magnetometers
For more technical information, visit www.gemsys.ca
deviations in values such as would be encountered in a
moving survey.
N
N
For use with a base station (i.e. where the unit is
stationary and not affected by large survey-related jumps
in the magnetic field).
AC Filtering controls whether 50 Hz or 60 Hz filters are added for suppression of noise from
powerlines. The final value discussed in this section is the Display Mode which is used to control
the appearance of the data onscreen while the survey is being performed.
16.
Move the cursor to the tuning menu item and select C-change. The system displays the tune
initialize screen. Set the value to yes by pressing the C-change button.
17.
Then press F-ok to exit. The system displays the autotune screen. Set the value to yes by
pressing the C-change button. The system returns to the Survey menu.
18.
Move the cursor to the AC filter item and select C-change. The system changes between
three values: no, 50 Hz and 60 Hz. Select the one that you want to use.
19.
Move the cursor to the display mode item and select C-change. The system shows the
display-mode screen and the current setting (either text or graph). If you:
•
Select text and F-ok, the system automatically returns you to the Survey menu after your
selection.
•
Select graph and F-ok, the system adds a second value: field nT. This means that the
field value will also be displayed. You can use the C-change button to select from other
labeling options such as coordinates, field nT & coordinates or no text.
When you press F-ok again, the system displays the clear graph screen. For continuous
plotting of values, leave this value set to no.
When you press F-ok again, the system displays the vertical scale screen. Use the C and
D keys, and the A- and B+ keys to change the base line position and the vertical scale of
the graph, respectively.
1.1.5 Working with the GPS Functionality
The GPS functionality is accessed with the Main survey screen and specifically, the F-GPS control.
Once you have turned the GPS functionality on, you will see a GPS screen with the following four
values:
•
A-initialize. Manual initializing of GPS. Normally GPS is initialized when you start the
survey; however, if you experience a situation in which the GPS is not responding, you
may want to try to manually initialize the GPS.