Schonstedt SPOT, Инструкция по эксплуатации

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Strongly Magnetized Markers
A strongly magnetized marker, at or near the surface, provides a weaker indication on both
sides of the marker that could be mistaken for the marker.
In Figure 8, the heavy line represents the increase and decrease in the audio signal
frequency as you move the locator over a marker. Between points
A and B, the signal
increases slightly and then decreases. Just beyond B, the signal increases rapidly, peaks
directly over the marker and then decreases at point C . From C to D , the signal increases
and decreases again. Therefore, if you do not move the locator completely across the
marker, you may assume that
the weaker indication on
either side of the marker is its
location. The two weaker
indications occur because the
locator is extremely sensitive
to the magnetic field
components parallel to its
long axis. At points
B and C ,
the field is perpendicular to
the locator, so no significant
audio indication is produced
at these points.
Figure 8: Signal Pattern from a
Strongly Magnetized Marker
Correct Stake Orientation
When placing stakes, correct orientation is important. For
verification purposes, the orientation of the pin relative to
the locator is shown in Figure 9. Check the pin with one
orientation, and then rotate the pin 180°. The orientation
which gives the largest reading is the one that should be
used.
An iron pin has two types of magnetization. One is the
magnetization induced by the Earth's magnetic field; the
induced magnetization is always downward in the
Northern Magnetic Hemisphere. The other type of field is
the permanent magnetization, which is fixed to the pin.
For maximum detection, the stake should be driven into
the ground so that the permanent magnetization is in the
same direction as the induced magnetization.
Fig ure 9: C he c king a
Sta ke ’ s O rie nta tio n