O R E N Z
P U L S E 5
29
5. Operating Procedures II (Target Classification
)
This chapter is a kind of summary how to proceed
with the LORENZ PULSE 5, when locating metal,
while using target classification, intensity meter
reading and the audio.
It is therefore possible to predertermine the exact
position, the detection depth as well as the kind
of metal located, without digging it out.
A specially developed electronic circuit makes
conductivity meter readings possible which are
directly displayed on a meterscale (0-100). Those
conductivity readings are only known from TR-
Machines but not from metal detectors based on
the pulse induction principle.
Please proceed as described in chapter 4 and
follow those additional instructions listed below.
Two person operation is necessary when using
frame mounted coils. The coil has to be hold with
two adjustable carrying straps at a constant height
of about 8” inches (20 cm) over the ground. The
search mode can now be selected with the mode-
control. The following described metal classification
facility can be selected in position disc. Before
starting to search it is advisible to adjust the
threshold of the audio.
For most detection purposes the audio and freq.
control can be put to the marked mid-position.
When having done this it is important to retune
the electronics with the zero-control. Proceed as
described in chapter 4 and hold the searchcoil or
frame over the ground while pressing the zero-
pushbutton for about 3 seconds.
When lowering the searchcoil to the ground an
increasing ticking-rate of the audio can be audible
in some cases.
This can either be generated by a metal object or
mineralized ground. When expecting mineralized
grounds the searchcoil can simply be raised again,
4-20” inches (10-50 cm) depending on the coil or
the LORENZ PULSE 5 can simply be tuned to the
ground conditions while holding the coil at a
constant height and pressing the zero-control for
a second. Pay special attention to metal objects in
the near of the searchcoil which may cause false
signals and therefore a false retuning process.
Note:
It is always advisible to carry the detector
with the supplied leather bag as far away from
the searchcoil as possible. This is absolutely
necessary to avoid false signals caused by metal
parts of the electronics control-box.
The searchcoil should be held at a constant height
while searching. In many cases it is advisible to
search in a systematically manner with a certain
grid which can be marked on the ground for
example.
The small 10” inch (26 cm) diameter searchcoil
can be supplied with a telescopic pole which is
held at constant height in parallel to the ground.
It is moved from side to side with overlapping
tracks to detect even the smallest coins which can
sometimes only be detected in the center of the
searchcoil as this is the most sensitive part.
Although the response speed of the LORENZ PULSE
5 is very fast, the search speed should not exceed
80” inches (2 m) per second.
When a metal object is located try to find the place
with the strongest signal, that means highest
indication on the meter in position 1, 2, 3 and
highest audio frequency. Size, shape and depth
informations can be derived from the audio sound.
Small objects like single coins will be indicated
with a short and intensive signal when a 10” inches
(26 cm) coil is used.
Coins and nails and very small pieces of metal will
cause two indications when passing them with a
frame mounted searchcoil (1 m x 1m) for example.
This is mainly because those small objects are out
of the range of the large coils and therefore will
only be indicated at the edges of the frame
mounted cablecoils and only when they are very
closed to it. Large metal objects will give an
extensive signal, and therefore can easily be
identified.
Deeply buried metal objects will generate a weak
and slowly increasing audio sound and intensity
meter reading, objects which are closed to the
surface can be identified by the strong and fast
increasing signal.
Large objects will cause a signal with a long
duration especially when located with large frame
mounted cable coils. A metalbox can give a signal
up to 230” inches (6 m) of duration when using a
80” x 80” inches (2 m x 2 m) coil. It is therefore
necessary to find the exact location of a buried
object. This is achieved by moving the coil from
different directions slowly towards the strongest
indication. In many cases it is of great help to use
an additional smaller coil when pinpointing a
target. The center of the searchcoil is always the
most sensitive part.
