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OPERATING IN ALL - METAL MODE
The All-Metal mode is more sensitive than the Discrimination mode, and is used to
find all types of metal objects in the ground. The searchcoil must be in motion for
objects to be detected.
Ground Grab (GG)
Naturally occurring minerals in soil look like metal to a metal detector, so you want to
cancel out this mineral signal coming from the ground, and only detect the signal from
metal objects in the ground.
So before using your detector, set it in All-Metal mode and perform the automatic
ground balancing procedure. Press-and-hold the GG button while pumping the
searchcoil up and down over the ground. Release the button when the sound evens
out. The GND BAL number on the bottom right of the screen is the detector’s internal
setting which cancels out the minerals in the ground. Different soils in different areas
will require different GND BAL settings, so balance to ground before you search. See
the section on Ground Balancing for a detailed description of this procedure.
Refer to the Ground Balancing section of this manual for a more in-depth description.
Setting the Controls
As you adjust any of the controls, notice that the values on the bottom-right of the
display indicate the settings of the value you are changing.
If you are new to metal detecting, start with the GAIN and THRESHOLD controls at a
low enough setting that you do not hear too many unwanted sounds, like warble or a
loud hum. Set the GAIN at the 12:00 position, or less. Then set the THRESHOLD to a
position where you hear a very slight background hum, or if you prefer, dial the control
just left of that position to a setting where the detector is silent.
Unwanted Noise
Read the section on Electrical Interference.
The G2 is a highly sensitive device.
It is intended for use outdoors. Indoor operation will subject it to electrical interference
from a wide variety of devices in the home or office.
Sweeping the Searchcoil
As you sweep the searchcoil over the ground, try to keep the searchcoil parallel to the
ground.
Avoid lifting the searchcoil at the end of your sweeps.
Operating in All-Metal Mode continued on next page
Understanding ground conditions assists the user in setting up the machine,
knowing when to readjust ground balance, and in understanding the responses
of the machine while searching.
This detector displays two kinds of ground data:
1. The type of mineralization (which affects where the ground phase should
be set). This is GND PHASE
2. The amount of mineralization (the greater the amount of mineralization,
the greater the loss of detection depth & ID accuracy; this loss is more
pronounced in Discrimination Mode). This is Fe
3
O
4
.
The goal of ground balancing is to equate the GND BAL number to the
PHASE number.
PHASE is the measurement of the ground.
GND BAL is the detector’s internal setting which calibrates the detector
to the ground’s phase.
Notice that the GND BAL number is three digits, with a decimal point.
PHASE has only two digits.
GND BAL is a higher resolution number, so may differ a bit from PHASE
in a perfectly balanced scenario.
After pumping and releasing GG, the exact measurement of the ground
will be transferred to the GND BAL setting.
The two-digit PHASE number displayed on the screen indicates the type of
ground mineralization.
Some typical ground mineralization types are:
0 – 10 Wet salt and alkali
5 – 25 Metallic iron. Very few soils in this range. You are probably over metal.
26–39 Very few soils in this range -- occasionally some saltwater beaches
40–75 Red, yellow and brown iron-bearing clay minerals
75–95 Magnetite and other black iron minerals
Ground Balancing continued on next page
GROUND BALANCING