Fisher Research Labs Gold Bug Pro, Owner'S Manual

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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 Ground Grab
®
CoMPuTErIZED
GrouND BALANCING (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
OPERATING IN DISCRIMINATION MODE
Discrimination is used to eliminate trash metal objects (e.g. nails, foil, pull-tabs) from
detection. The searchcoil must be in motion to detect metal. The Discrimination
Mode is less sensitive to small and deep objects than the All Metal Mode.
Ground Grab ® COMPUTERIZED GROUND BALANCING
This feature is not available in Discrimination Mode.
Your best results will be achieved by first performing the CoMPuTErIZED GrouND
BALANCING procedure in All Metal Mode.
The ground balance setting achieved using CoMPuTErIZED GrouND
BALANCING will carry over into this mode.
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.
GAIN
If you are new to metal detecting, start with the GAIN at a low enough setting that you do not
hear any sounds when the searchcoil is sweeping across the ground, with no metal present.
Start with GAIN at the 12:00 position, or less.
In this mode, Gain refers to the detector’s sensitivity. The higher the setting, the deeper
objects can be found, and the more sensitive the detector is to very small metal objects.
MODE
The right knob is not used in the Discrimination Mode.
Click the right knob 100% counterclockwise.
If you turn the knob to the right, you will leave Discrimination Mode, entering All Metal Mode.
DISC LEVEL
Press
+
to eliminate unwanted metals from detection.
Each time you press
+
the Disc Value at the bottom-right of the display will increment by
one.
Press-and-hold
+
to increase the Discrimination level rapidly.
See the Target Identification section of the manual for a detailed description of this function.
Sections of the arc with no indication represent metals completely eliminated from detection.
Sections of the arc with a lightly shaded indication represent metals detected with
a low tone.
Press
–
to detect metals which were previously eliminated from detection
Unwanted Noise
read the section on Electromagnetic Interference.
This 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.
In Discrimination Mode, when you sweep the coil over the ground it will usually be
quieter than when holding the detector still.
Sweeping the Searchcoil
As you sweep the searchcoil over the ground, try to keep the coil parallel to the ground.
Avoid lifting the searchcoil at the end of your sweeps.
Operating in Discrimination Mode continued on next page