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The goal of the Ground Balancing procedure is to eliminate the sound as the
searchcoil is being pumped over the ground. In some soils, the sound is not
completely eliminated.
After balancing to ground with Ground Grab
®
CoMPuTErIZED GrouND
BALANCING (GG) some users may want to further adjust the ground balance
point manually.
To manually adjust ground balance:
1. operate in ALL METAL Mode.
2. Pump searchcoil up and down over the ground as in the
CoMPuTErIZED GrouND BALANCING procedure.
3. Press
+
or
-
while pumping
If the ground balance adjustment is incorrect, there will be a difference in the
sound as the searchcoil is either moving toward or away from the ground. It
sounds like you are either
pulling the sound out of the ground,
or
pushing
the sound into the ground.
•If the sound is louder as you raise the searchcoil, increase the ground
balance setting.
•If the sound is louder as you lower the searchcoil, reduce the ground
balance setting.
NoTE: Experienced users often prefer to adjust the ground balance to get a
weak but audible response when lowering the searchcoil. This is called
adjusting for positive response.
POSITIVE AND NEGATIVE RESPONSE
The purpose of ground balancing is to adjust the metal detector to ignore ground
minerals. If the setting is incorrect, ground minerals will give either a
positive
or
a
negative
response, depending on which direction the adjustment is off.
Positive Response
If the GND BAL setting is too high a number, the response of minerals will be
positive
. This means that when the searchcoil is lowered to the ground in
PinPoint or All Metal Mode, the sound will get louder as the searchcoil
approaches the ground. The sound will grow quieter as the searchcoil is raised.
What, if anything, you will hear in Discrimination Mode depends on the
discrimination setting.
When searching in an All Metal Mode, if ground balance is properly set to cancel
the ground, and you sweep over a
positive hot rock,
the rock will give a “zip”
sound similar to that of a metal object.
Negative Response
If the GND BAL setting is too low a number, the response of minerals will be
negative.
When the searchcoil is lowered to the ground in PinPoint or All Metal
Mode, the machine will be silent. The machine will sound off as the searchcoil is
lifted away from the ground. What, if anything, you hear in Discrimination Mode
depends on the Discrimination setting.
When searching in All Metal Mode a
negative hot rock
will produce a “boing”
sound after passing over it, making it difficult to know where it is located. It will
not have the sound and “feel” of a metal object.
GROUND BALANCING
Reading the Display
Most gold prospecting and relic hunting is done by ear. Listen for the louder sounds,
riding on top of the constant background hum.
As you sweep the searchcoil, notice the
Fe
3
O
4
(iron oxide) scale to the left of the
display.
This indicates the
amount
of ground mineralization.
Most black sand is made of magnetite.
Gold nuggets are often found in concentrated black sand deposits.
For the best depth detection in highly mineralized soils, use the All Metal Mode.
For the most accurate Fe
3
o
4
reading, pump the searchcoil over the ground.
While sweeping the searchcoil, also notice the
GND PHASE
value in the middle of
the screen.
GND PHASE is the ground phase; this indicates the
type
of minerals in the soil.
Within an area, the ground phase may change.
After ground balancing, periodically compare GND PHASE to GND BAL. If these
two numbers differ by a great deal, you may want to ground balance the detector
again.
When not adjusting the knobs, the
GND BAL
setting will always appear on the
bottom-right of the display.
GND BAL is the detector’s internal ground balance setting. The detector’s default
ground balance setting is 82.9, which is the best starting point for achieving the
correct setting.
After you perform the Ground Grab
®
procedure, the GND BAL number will
change to match your soil.
You can change the current GND BAL setting by pressing the
+
or
–
buttons.
See section on Ground Balancing for a more detailed explanation.
Experienced users often prefer to adjust the ground balance to get a weak
audible response when lowering the searchcoil to the ground. This is called
adjusting for positive response
and is achieved by increasing the GND BAL
number with the
+
key.
Target Scale
The arc across the top classifies metal objects.
Each time a target is detected, three segments will illuminate above the arc.
The segments will remain illuminated for three seconds.
This indication shows the approximate classification of the buried metal object.
See the section on Target Display for a more detailed explanation.
Iron is on the left. u.S. dimes and quarters are to the far right.
In an air test, gold indicates right of center -- the larger the gold piece, the
farther to the right.
In the ground, the ID of gold may jump around with each pass of the searchcoil.
If searching in All Metal Mode, you may want to switch back into Discrimination Mode, after
finding a target, to see a more accurate target identification, viewing the 2-digit Target-ID
OPERATING IN ALL METAL MODE
Summary of Contents for Gold Bug Pro
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