Selective Metal Detector SOREX PRO. Operating manual.
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Visual Identification Tool - Hodograph
In the hodographic image mode target
information is shown as a vector on the
graph with axis Х and Y.
Its size, form and angle depend on the
electric parameters of objects such as
conductivity, magnetic penetration, depth,
geometry etc.
It is almost impossible to describe all
nuances, understanding comes with step-by-step progress in visual image memorizing
and it depends on practical experience. But there are some consistent patterns which
may help you to start the capture, such as:
1.
Hodographs of small and medium objects made of iron are located in the left
half of the screen. In other words, they deflect to the left from the centre of the
horizontal axis along the bottom border of the screen.
2.
Hodographs of nonferrous metal objects in most cases are located in the right
half of the screen. In other words, they deflect to the right from the centre of
the horizontal axis along the bottom border of the screen. Rarely, small low-
conductivity metal objects as well as nonferrous objects masked by iron objects
may give hodograph in the left half of the screen, but with a great deflection
from the zero. (to – 35 VDI). Hodographs of large iron objects (helmet, axe, tin
plate) also appear in the right half of the screen.
3.
Larger reflection surface and higher conductivity of the object give stronger
hodograph inclination to the right. For instance, with equal diameter and
thickness, copper coin hodograph would be closer to the horizontal axis than the
bronze coin hodograph. That happens because copper conductivity is higher
than bronze alloy conductivity.
4.
Hodographs of medium and large iron objects of non-round shape often have a
form of wide loop, located both in the left and in the right half of the screen
simultaneously. Hodographs of nails, arrow heads and other small iron objects
have a shape of straight vectors in the left half of the screen.
5.
Hodographs of nonferrous metal objects in most cases have straight shape or a
narrow loop shape in the right half of the screen.
The advantage of hodographic indication over
VDI
Two representative target
hodographs are shown on pictures.
These objects (a coin and a piece of
rusty tin) give a nonferrous signal on
all similar devices.
In both cases target VDI would be +76.
It is seen in hodograph shape only that in first case (left picture) the target is sure to be
nonferrous.
Nail
Grenade F 1
-
Foil
Tincan Coin
mm
15
Ø
Coin
mm
25
Ø
Drain hatch