rear controls
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4 controls and operation – rear
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Boost (Shallow/N/Deep)
Boost switch selects the type of processing and filtering applied to
the detector signals to enhance different target signals in different
circumstances.
•
N (Normal)
mode may be used for general detecting conditions.
This does not boost any signals.
•
Shallow
mode boosts signals from small targets close to the
surface.
This makes faint target signals easier to hear. This setting may also
boost some ground noise, therefore Shallow is better suited for
'quiet' ground conditions or for pinpointing tiny targets.
•
Deep
may be used when searching for large targets at greater depth
in 'noisy' ground. Random soil signals are smoothed, making small
changes in the audio signal from large deep targets easier to hear.
This may mask some signals from very small targets near the
surface.
Selection of the more suitable position should be after considering both
the expected target size/depth and ground conditions.
NOTE – When Boost is changed, Threshold may also need to be
adjusted. External amplifiers may be used in addition to the Boost
switch, provided that they have loudness limiters built in. This
prevents loud signals becoming unpleasant or dangerous to the
user's hearing.
Figure 4.14
Boost switch
rear controls
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4 controls and operation – rear
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GP 3500
GP 3500
www.minelab.com
page 19
Soil (Sensitive/Normal/Salt)
This switch is used to optimise the detector for different soil conditions
and targets by changing the signal processing.
Operating Instructions:
•
N (Normal)
mode may be used in all areas, including areas with
highly mineralized soil. This position has very good sensitivity to
a wide range of nugget sizes and is the most versatile of the three
positions.
•
Sensitive
mode may be used when searching for small nuggets,
especially in areas with highly mineralized soil. The extra stability
allows the coil to be used closer to the ground in areas of excessive
ground noise. Sensitive may not work well if the ground is salty.
This setting may reduce the depth at which large nuggets are
likely to be found.
•
Salt
mode may be used in areas containing a high salt content,
be they neutral or heavily mineralized. In highly mineralized
areas without salt, this setting may be less sensitive to small
nuggets than Normal or Sensitive settings, but the difference to
large targets is marginal
Figure 4.15
Soil switch
(Normal/Sensitive/Salt)
