9.
practising the controls
p26
9. Practising the Controls
Take some time to become familiar with how the Sovereign GT responds to various metal objects.
a)
Gather a collection of different metal objects such as a rusted nail, pull-tab, brass button,
aluminium foil, various coins, and some gold and silver jewellery.
b)
Take the detector outside, away from known electromagnetic devices or metal objects. Lay the
various objects out on an area of ground known to be void of other metal objects.
c)
Switch the Sovereign GT On and select Disc. Mode.
d
) Turn the Disc and Notch controls to their most anti-clockwise positions.
e)
Turn the Sensitivity control to "maximum", the most anti-clockwise position without clicking into
Auto. If excessive interference is heard, turn the Sensitivity control clockwise until the threshold tone is
stable.
f)
Pass the coil across the test objects one at a time. The Sovereign GT should "beep" on the
non-ferrous objects and ignore the ferrous objects.
g)
Take note that as the coil passes over the ferrous nail, the threshold tone disappears. As the
threshold returns it will have a lower than normal pitch, indicating that the object ignored was ferrous.
h)
Passing the coil over different non-ferrous objects will produce different signal tones. Objects with
high conductivity, such as those of silver or copper, will produce a high-pitched signal tone while
objects with lower conductivity, such as aluminium foil, will produce a low-pitched signal tone. With
experience it will be possible to use the signal pitch from an object to accurately determine the type of
object discovered before recovering it from the ground.
i)
Turn the Disc control progressively clockwise in small steps and pass the coil over the objects. Take
note of when certain objects are rejected; this will enable more accurate discrimination of these objects
in the field.
j)
Turn the Disc control to the position where it ignores the pull-tab. Passing the coil over objects with
lower conductivity (such as the aluminium foil) will not produce a signal. Take note of the threshold tone
as it disappears, then returns again. It should return at a slightly different pitch than normal. This
indicates that the Sovereign GT ignored a non-ferrous object.
k)
Turn the Disc control back to the most anti-clockwise position.
l)
Progressively turn the Notch control in a clockwise direction, again passing the coil over the test
objects. The Notch control enables the detector to ignore a small number of objects with similar
conductivity while still detecting other valuable non-ferrous objects, even if they are of
lower conductivity.
m)
Turn the Notch control to ignore the pull-tab. Objects with similar conductivity to the pull-tab will be
ignored. Pass the coil over the aluminium foil and the Sovereign GT will produce a signal. This would
not be possible using the Disc control.
n)
Turn the Disc control to ignore the aluminium foil. The Sovereign GT is now set to ignore the types
of objects most commonly unwanted by treasure hunters.
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10.
treasure hunting tips
www.minelab.com
p27
10. Treasure Hunting Tips
The Sovereign GT will perform at its best when
its Tornado coil is kept in close proximity to the
ground. Inexperienced operators should practice
maintaining a constant coil height at the
extremity of each swing; maintaining contact with
the ground will make this easier. This is important,
as variation in coil height at the end of each swing
can cause confusing sounds and will reduce
detection depth.
NOTE:
Each sweep of the coil should overlap the
last one. This will ensure good ground coverage.
Keeping the Tornado coil in contact with the
ground will increase detection depth and improve
the audio response to small objects.
10.
1.
Pinpointing the Target
When the approximate location of the target has been determined, move the coil slowly over the
target. The audio signal will increase in volume while moving towards the target and decrease in
volume as the coil is passed away from it. The signal will be loudest when the coil is directly over the
target. Quite often the detector will be producing its maximum volume for a broad area over the
target. This generally indicates that the target is near the surface or is quite large.
To receive a sharper, more precise signal over the target, it may also be beneficial to switch to the
All Metals and Pinpoint modes as this will produce a narrow response to the target. (see p.21)
The open design of the Tornado coil makes it easy to mark the ground directly above the target to
aid recovery.
Figure 18
- Sweeping
the coil
Figure 19
Pinpointing the target
