Minelab GPX 5000 Instruction Manual page 43

Note: Use this procedure to
periodically test that you are
effectively compensating for
ground noise.
Ground Balance reset in Tracking
While detecting in Tracking you should periodically test that
you are still in harmony with the ground by stopping, then
raising and lowering the coil. If the Threshold remains stable
then you are still Ground Balanced. If there is a change in the
Threshold then you need to reset the Ground Balance setting.
Do this by continuing to raise and lower the coil, or repeat the
procedure on p. 40.
While raising and lowering the coil press and release the
Quick-Trak button. A short 'beep' will be heard which lets you
know that a three second, fast auto-Ground Balance is initiated
prior to returning to Tracking. Once the audio has stabilized
you can continue searching.
If you find that the Ground Balance needs to be reset quite
regularly, you can select a Faster Tracking speed. Three
Tracking speed options (p. 70)
LCD menu.
Note: In highly variable ground the Tracking may not
instantly update the GB setting when you detect over a large
mineralisation change; so there may be a period of time where
you will experience some ground signals. To avoid missing any
faint target signals you may have to reset the ground balance,
and slow down your detecting sweep speed to allow the
Tracking to keep up with the ground variations.
As Tracking continually updates the Ground Balance
setting, repeated sweeps over a metal target may result
in the detector balancing to the target instead of the
ground; thus diminishing the target signal and increasing
ground noise. Therefore, it is important to use Fixed when
pinpointing or when investigating a potential faint signal
with repeated sweeps.
are available from the
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