Minelab GPX-4500, Instruction Manual

Page: 24 / 55

42 43 Ground Balance Procedure
for Fixed
(For Ground Balance Type – General)
1 Find a clear area of ground without any targets.
2 Change the Ground Balance switch to Fixed.
3 Whilst keeping the coil parallel to the ground, lower
and raise the coil between 25mm and 100mm
(1" and 4") over the ground. Try to lower the coil as
close to the ground as possible without touching it.
4 While moving the coil press and hold the Quick-Trak
button. The Tracking program initiates a very fast
Ground Balance for a short time.
Note: This is the same effect as changing the Ground
Balance switch to Tracking on the front panel.
5 Continue moving the coil up and down until the
ground noise has stopped. When there is no longer
a change in the Threshold the detector is
‘Ground Balanced’.
Note: A persistent signal may indicate a target in the
ground. If this occurs, then move the coil to a new
location and repeat the procedure.
6 Release the Quick-Trak button to return to the Fixed
position and commence detecting.
Ground Balance reset in Fixed
Whilst sweeping the coil to test if you are still in
harmony with the ground stop, then raise and lower
the coil. If the Threshold remains stable then you
are still ground balanced. If there is a change in the
Threshold you will need to reset the Ground
Balance setting.
This is achieved by simply repeating steps 3–6 of the
Ground Balance procedure for Fixed.
Ground
Balance
Tracking
Fixed
Ground Balancing Tips
When going over old patches (i.e. small concentrated areas known to have
produced gold nuggets) run in Fixed Ground Balance and periodically
re-Ground Balance with the Quick-Trak button every few metres.
When Ground Balancing in very rocky terrain lower the coil to the height
above the ground you will actually be swinging at.
In highly magnetic soils you may have trouble ground balancing the coil all
the way to the ground (most common with larger Monoloop coils). If you
experience this you can change the Ground Balance Type to Specific; which
requires a different ground balance procedure
(pg. 60) .
Note: When searching in
Fixed it is very important
to regularly check the
Ground Balance and reset
when required. Testing, by
raising and lowering the
coil, is quick and simple and
should become a regular
part of your detecting
technique.
100mm (4")