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GSM19 Series Magnetometers - Version 7
GEM Systems, Inc. Advanced Magnetometers
For more technical information, visit www.gemsys.ca
4. INSTRUMENT DESCRIPTION
Before starting, you should be aware of some general terminology that applies to GEM’s
magnetometers and gradiometers. ROVER and BASE station modes are terms that describe the
operating characteristics of instruments whereas SLOW and FAST reading rates describe the
cycling characteristics of instruments. Specifically,
•
ROVER mode refers to instruments that physically move throughout the survey. GEM delivers
instruments that operate in mobile (i.e. magnetometer), gradiometer, walking magnetometer and
walking gradiometer modes.
•
BASE station mode describes stationary units used for diurnal correction.
•
SLOW cycling rates describe instruments that cycle from 3 seconds to 1 hour.
•
FAST reading rates describe instruments that cycle from 0.5 seconds to 1 hour (i.e. include all
SLOW reading rates).
By default, all GSM-19 series magnetometers / gradiometers have a mobile and base station mode,
and cycle at a slow reading rate. However, if you purchase additional options such as walking mode
or walking gradiometer rover mode, your instrument is automatically upgraded to a fast cycling
rate.
Please keep this terminology in mind when reading the next two sections and other parts of the
manual that describe the various operating modes and options.
4.1 STANDARD SYSTEM COMPONENTS
The following images show the standard components that are shipped with a GSM-19 system.
Figure 2. GSM-19 Case with Sectional Staff rods. Assemble these rods if you
are planning to conduct a “Mobile” survey (i.e. one with discrete
stations as opposed to a “walking” or continuous survey).