1
1
2
2
7
7
.
.
Notice that the position of the KNOB affects
the sound relative to the coil’s direction:
a
a
.
.
If you hear a louder sound as the
searchcoil is
lowered toward the ground,
we call this
positive response.
b
b
.
.
If you hear a louder sound as the
searchcoil is
lifted away from the ground,
we
call this
negative response.
8
8
.
.
Rotate the knob both clockwise and
counterclockwise while pumping
the coil and notice the KNOB
position where the sound
changes from
negative
response
to
positive response.
9
9
.
.
Set the KNOB at the position
where you achieve a
slight
positive response.
i.e. the sound is slightly
louder as the coil is
lowered toward the
ground.
C
C
A
A
U
U
T
T
I
I
O
O
N
N
:
:
cannot ground balance over a metal object.
A
A
l
l
t
t
e
e
r
r
n
n
a
a
t
t
e
e
Q
Q
u
u
i
i
c
c
k
k
G
G
r
r
o
o
u
u
n
n
d
d
B
B
a
a
l
l
a
a
n
n
c
c
i
i
n
n
g
g
M
M
e
e
t
t
h
h
o
o
d
d
You may also use the following, simpler method, to ground balance.
While not as accurate as the coil-pumping method in AutoTune, it
yields an approximate ground balance setting.
Find a patch of ground free of metal
1
1
)
)
Set the ground-balance knob at the pre-set position, 100%
clockwise.
2
2
)
)
Position the searchcoil about 6” over the ground.
3
3
)
)
Press PINPOINT button
4
4
)
)
Lower searchcoil to within 1” of the ground. Sound will get louder.
5
5
)
)
Rotate knob slowly counterclockwise until detector is just silent.
6
6
)
)
Rotate knob back slightly clockwise until you hear a low volume
sound. At this low-volume setting, the detector is approximately
ground balanced.
GROUND BALANCING
(continued)
1
1
3
3
GROUND BALANCING
What is Ground Balancing?
Why do I need to Ground Balance?
All soils contain minerals. Signals from ground minerals are often tens or
hundreds of times as strong as the signal from a buried metal object.
The magnetism of iron minerals, found in nearly all soils, causes one
type of interfering signal. Dissolved mineral salts, found in some soils, are
electrically conductive, causing another type of interfering signal.
Ground Balancing is the process by which the metal detector cancels
the unwanted signals coming from the ground minerals while still
detecting the signals from buried metal objects. This is accomplished
by calibrating the detector’s phase response, eliminating the signals
from ground minerals.
When the detector is calibrated to the soil, the result will be deeper
target detection, quieter operation, and more accurate target
identification.
H
H
o
o
w
w
t
t
o
o
G
G
r
r
o
o
u
u
n
n
d
d
B
B
a
a
l
l
a
a
n
n
c
c
e
e
y
y
o
o
u
u
r
r
d
d
e
e
t
t
e
e
c
c
t
t
o
o
r
r
:
:
(
Preferred method
)
Find a patch of ground free of metal
1
1
.
.
Rotate the G
G
r
r
o
o
u
u
n
n
d
d
-
-
B
B
a
a
l
l
a
a
n
n
c
c
e
e
K
K
N
N
O
O
B
B
100% clockwise to the Preset
position.
2
2
.
.
Press the A
A
U
U
T
T
O
O
T
T
U
U
N
N
E
E
pad. ALL-METAL appears on the display.
3
3
.
.
Press S
S
e
e
n
n
s
s
i
i
t
t
i
i
v
v
i
i
t
t
y
y
+
+
pad several times to reach the highest “quiet”
setting or a setting with a
faint background hum.
4
4
.
.
Press T
T
h
h
r
r
e
e
s
s
h
h
o
o
l
l
d
d
+ o
o
r
r
– to
adjust the audible hum to a
comfortable level.
5
5
.
.
Physically
pump
the
searchcoil and detector up
and down over the ground.
Lift the searchcoil about 6
inches above the ground
and lower it to within 1 inch
of the ground, about once
or twice a second.
6
6
.
.
While pumping the
searchcoil over the ground
in this fashion,
slowly
rotate the KNOB counterclockwise.
F4manual-SPREADS(24pg).qx 4/13/11 8:30 AM Page 12
