White’s Electronics Goldmaster GMT - Manual (Page 16)

14
GROUND BALANCE
TOGGLE SWITCH
-
The GMT has an exclusive new digital system that
records the AMOUNT
of mineral in the ground. A
reference number in the upper right portion of the
display shows this value. The number grows as the
coil is pumped up and down over concentrations of
black sand. As most electronic prospectors have
always known, gold usually follows black sand. So
with the new GMT you can avoid the problems that
varying TYPES of ground mineralization cause by
tracking out the mineralizatioin, but at the same
time use the AMOUNT of magnetic effect in black
sand to locate concentrations of mineralization
where gold might concentrate. This would be a way
to follow a stream bed for black sand or locate hot
spots to use a dry washer in the desert.
An added feature for GROUND BALANCE cali-
bration is the GRAB PAD. In both MANUAL
and
FAST AUTO TRACK mode you can quickly reset
GROUND BALANCE by pressing and holding the
GRAB PAD and pumping the searchcoil up and
down ONCE. The microprocessor controlled
circuitry will instantly jump to GROUND BAL-
ANCE. This feature is extremely handy when you
have AUTOTRACKED a HOT ROCK and want to
get searching again. In MANUAL mode, the
GRAB PAD can give you a head start on using the
plus (+) and minus (-) pads for your initial
GROUND BALANCE calibration. While searching
in MANUAL mode, pressing and releasing the
GRAB PAD updates the manual ground balance
setting instantaneously (you may fine tune with the
(+) touch pad)
Ground Balance
Fast Auto Trac
Gold is usually found in mineralized ground. To
make it easier to track out the mineralized ground,
the GMT has an automatic ground balance capabil-
ity called FAST AUTOTRAC. Set the GROUND
BALANCE toggle switch in the Initial Setting or
UP position. The default GROUND BALANCE
reference value of 77 (ferrite) will show in the
upper LEFT portion of the display. The number
represents the TYPE of mineralization in the
ground, higher numbers for negative ground (black
sand and magnetite) and lower numbers for posi-
tive ground( maghemite and alkalai soil). Start your
search by swinging the searchcoil in wide sweeps,
overlapping the search area as you go. You may
notice that the GROUND BALANCE reference
value will be changing as the GMT automatically
tracks out the mineralization. However, the refer-
ence number may stay the same because the dis-
play numbers only go from 0-99 while the tracking
system itself has a resolution of 1 part in 4,000.
AMOUNT OF MINERAL
REFERENCE NUMBER
GRAB PAD
Chapter 4 GMT Controls
GROUND BALANCE
REFERENCE NUMBER