Minelab E-TRAC Manual page 8

Sensitivity Modes
Now for a bit of Physics!
E-Trac has three sets of internal signals used to identify targets. E-Trac continually measures the magnetic
ground interference that a ects these signals and adjusts the level of Sensitivity individually for each set of
signals, to provide the most stable Target ID.
Most ground types cause some interference and E-Trac uses this to adjust the detector to the correct Auto
Sensitivity.
Auto Sensitivity may not work well on the wet and transition areas of salt water beaches (it would be ne
on dry sand areas) as they do not typically contain magnetic materials.
Note: Minelab recommends beginners use E-Trac in the Auto Sensitivity mode unless detecting on a beach
where Manual is recommended.
A completely new feature, the Sensitivity Gauge has two indication bars in both Auto and Manual and a
numeric Sensitivity value above the gauge.
Manual Sensitivity (M)
The left bar and numeric value indicates the level of Sensitivity you have set.
The right bar indicates the 'Suggested' Sensitivity level the same as it does in Auto (A)
The important di erence between Auto and Manual is that all of the 3 channels (H, M & L) are set to the
same level in manual and if set too high may cause unstable target ID's.
For example, if the Suggested Sensitivity determined by the detector is 15 and you set Manual Sensitivity
to 20, all channels are set to 20. If one channel is a ected by the ground conditions then Auto would
normally reduce the level for this channel. In Manual it is not reduced and stays set to 20 so the ground
interference may cause false signals and unstable ID's.
Auto Sensitivity Range + 3 to – 3
The Sensitivity can be increased by + 3 levels or decreased by – 3 levels.
This innovative new feature allows you to be [more aggressive] or [conservative] while operating E-Trac
in Auto Sensitivity. Increasing by 1, 2 or 3 sets the Auto Sensitivity higher than the Automatic setting by
the number of levels you select. Similarly, decreasing would have the opposite e ect but bear in mind
sensitivity to smaller items could then drop o somewhat.
Auto sensitivity (A)
The left hand side bar indicates the highest Sensitivity level that either the high,
medium or low channel is operating in.
The right hand side bar indicates the "Suggested" Sensitivity level. This is an
average Sensitivity Level of the internal signals. Each internal signal is set to
a di erent level of sensitivity individually by the detector to provide the most
stable Target ID's.
For example, if E-Trac determines the Sensitivity Levels for each signal to be 20,
15 and 10, the left hand bar and the numeric value of the Sensitivity gauge will
display 20
The 'Suggested' Sensitivity (the right hand bar) will display the average of all
three channels, which will be 15.