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There are times, when searching in discrimination, that a target may be present in
one direction but not the other. In this case it is suggested to use the “
all metals
” mode.
This will often time help in locating these targets that may appear in direction and
disappear in another.
ABOUT THE PINPOINT MODE
As was already mentioned, the pinpoint mode serves to define the exact location
of the detected target. We will look at some suggestions for the proper use of the pinpoint
mode.
Having located a target in the standard search mode and deciding that it is worth
retrieving we now need to locate its precise location.
Move the search coil off to one side of the located target along the line A ( Fig.
37
).
Then activate the pinpoint mode.
As accurately as possible, while maintaining the distance between the ground and
the coil, scan the object left to right. Determine on line A the location (coordinate) where
the tone of the sound was the highest. Then take the coil from the sensing area
perpendicular to the primary direction (A) scanning (e.g. forward) along the line ( line B ).
Scan the object along the line as accurately as possible keeping a minimum
distance between the ground and the sensor. The recorded coordinate of the maximum
sound volume on line B, will determine the exact location of the object and will coincide with
the centre of a round window.
Fig. 37
46
