Cubic 156-PMD, Руководство по эксплуатации

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c. When a chirp is obtained, it does not always indicate the presence of a
mine, but could also be caused by tilting the search head, touching the ground or a
clump of wet high grass with the search head, passing over an area with ruts or ridges
on the surface, or by sudden variation of soil moisture or consistency. Investigation of
these various anomalies is further discussed in paragraphs d, e and f below.
d. Generally, if caused by tilting or touching the ground, it will not be
possible to get additional alarm indications (increases in click rate) over any particular
spot in the area where the chirp was first obtained. Thus, while in POINT mode, the
click
rate will remain low and automatic reset to SEARCH mode will occur after 3.5 seconds.
Start sweeping immediately after the low click rate stops and synchronize sweeps
again
with the metronome clicks, but always sweep again over the spot where the chirp was
previously obtained.
e. If a chirp is caused by touching a clump of high grass or by a surface rut
or ridge, the area around the clump should be investigated by slowly moving the search
head over the area surrounding the clump of grass while in POINT mode.
A repeatable increase in click rate indicates a probable mine.
Passing the search head over surface ruts or ridges is in effect the same as tilting the
search head and can cause a chirp. (Note that ridges can also be formed by the border
of a grassy
or
vegetated area).
As
mines could be buried in ruts or under ridges, these
areas should be investigated with the mine detecting set in the POINT mode, by
moving the search head in short sweeps parallel to the rut or ridge. If no increase in
click rate can be heard, the chirp was caused passing over the ridge. A mine should
resent a
alarm indication regardless of the direction of the sweep.
NOTE: It should be remembered that automatic transition from POINT to SEARCH
mode will occur after 3.5 seconds if no increase in click rate is periodically obtained
If more time is needed to investigate an area, the mine detector can be kept in the
POINT mode by tilting the search head, after about 3 seconds have passed without an
increase in click rate. This tilt method can also be used to force the mine detector into
the POINT mode when needed or desired to investigate an area suspected of possibly
hiding a mine.
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