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w w w . m i n e l a b . c o m
I D E N T I F Y I N G TA R G E T S I G N A L S
Pinpointing
To find an object, and reduce the size of the hole required to remove
it from the ground, it is necessary to pinpoint the exact location of the
object.
If a target is heard, first confirm it by setting an accurate ground balance
and then pinpointing. To ground balance, the coil should be passed
around the area of the target, making sure that the target is not detected
(keep the coil away from where the target is)
While the coil is moving around the area of the target, change
Balance to Fixed. This will give a very accurate 'ground balance'
on this area. One of the pinpointing techniques may then be used.
When a target is detected, sweep the general area with the coil,
taking note of where the strongest signal is received.
By shortening the length of the sweep it should be possible to draw
an imaginary line in the ground where the strongest signal is located.
Line up the target at 90° from the initial direction and repeat the
process. The object is located where the two imaginary lines cross
(see Figure 6.4).
Figure 6.4
Pinpointing technique
NOTE
Pinpointing will not locate a target in the centre of
the coil if operating with the RX switch set to Enhance or
Cancel.
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RECOVERING THE TARGET
When you are sure of the location of the target, it is
necessary to dig a small hole to recover it. In order to
preserve the environment, the hole should be as
small as possible. Always replace the soil and grass
which is removed.
It is essential to carry at least one of the following digging tools with
you when searching:
•
small, strong digging spade
•
pick
•
shovel
•
and crowbar (for very deep objects in hard ground).
STEP 1
Before digging, clear the area of loose surface material and
check that the target signal is still there. If it is not, the target
should be amongst the surface material.
STEP 2
If the target signal is still present, dig to a depth of approx.50mm.
STEP 3
If the target cannot be seen, sweep the coil over the hole.
STEP 4
If the target signal is not heard, then the target should be in
the pile just dug.
STEP 5
Check that there are no objects buried in the soil under the pile.
STEP 6
Take care when you dig, as damaging a nugget may reduce
its value. Start digging approx.100mm in front of the target to
reduce the chance of damage.
STEP 7
Pile the diggings carefully as it may be necessary to
search them.
STEP 8
If the target is located in the soil which was removed, sweep
the coil over the pile and pinpoint its exact position.
R E C O V E R I N G T H E TA R G E T
