Minelab 4901 - 0059 Metal Detector User Manual


 
21
Buried metal objects are referred to as
targets. Target signals contain ferrous
and conductivity information.
As the coil is passed over a target, the
detector digitally processes the target
signal and displays this as a number.
Target Identification (ID) is used to
distinguish one type of metal target
from another.
Target ID numbers range from -8 to 48.
Negative numbers represent ferrous
targets and positive numbers represent
non-ferrous targets.
The last detected Target ID stays on the
display until another target is detected.
If the detector passes over a target that it
rejects, the display will show two dashes
instead of a number.
Rejected segments appear as black, accepted
segments disappear altogether (allowing signals
from metal objects). The combinations
of accepted and rejected segments are called
Discrimination Patterns.
Ferrous targets are those that contain
iron (e.g. nails). They are generally
magnetic and are represented by the
left-hand side segments.
Desired and undesired targets may
appear anywhere along the
discrimination scale, e.g.
Desired ferrous target - Canadian coin
Undesired ferrous target - iron nail
Desired non-ferrous target - gold coin
Undesired non-ferrous target - pull-tab
Discrimination segments may be turned
on or off, rejecting or accepting certain
targets, respectively (Editing Discrimination
Patterns, pg. 25).
In addition to the Target ID, targets are
also represented as a particular segment
on a linear scale at the bottom of the
display.
Each discrimination segment represents
a level of conductivity and ferrous
content.
Non-ferrous targets are those that have
no iron content, such as gold, silver,
copper and bronze. Non-ferrous targets
are often higher in conductivity and are
represented by the right-hand side
segments.
PATTERN DISCRIMINATION SCALE
24 non-ferrous 4 ferrous
The X-Terra 70 has 28 ID segments.
The target ID’s range from -8 to 48,
increasing in steps of 2.
Discrimination segment
Each segment refers to a certain type of
metal signal. Segments can be turned off (to
accept targets) or turned on (to reject targets),
accepting or rejecting signals from the
corresponding metal objects.
Target ID
The numeric identifi er
of a particular metal
object underneath the
ground.
TARGET ID
20
Many of the screen diagrams in this
manual refer to the X-Terra 70 operating
in the default Coin & Treasure Mode.
Target ID Stability
The X-Terra 70 has a fine Discrimination
Scale, but this may result in some
instability of the displayed Target ID in
some areas with highly mineralised soil.
In these cases, the Target ID numbers
may be further stabilised by using the
Target ID Stabiliser. The Target Tone may
not always match the stabilised Target ID.
A grey icon on the diagrams in
this manual represents a fl ashing
icon on the detector.
Activating Target ID Stability
In the detection screen, press and hold
MODE AUTO for three seconds. The icon
will appear, indicating that Target ID
Stability is activated.
To de-activate Target ID Stability, press
and hold MODE AUTO for three seconds.
The icon will disappear, indicating that
Target ID Stability is de-activated.
Press and hold to
activate/de-activate
Target ID Stability.