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Once the target path has been located, the arrows at the top of the screen will indicate
the location of the target path in relationship to the receiver.
Note: When field distortion (due to congestion) is affecting the receiver the left/right
arrows may not coincide with the bar graph. Use the maximum numerical signal
strength to target the cable or pipe.
B. Directional Null (DirNull)
In DirNull mode, as the operator approaches the cable or pipe, the numerical signal
strength will increase then fall sharply as the receiver crosses the target cable or pipe.
The bar graph fills from both sides toward the middle and the receiver speaker volume
decreases. As the antenna moves off the target path, the bar graph opens, the signal
strength increases, and the speaker volume increases. Gain adjust is automatic in DirNull
mode.
The center of the DirNull screen provides a ‘compass view' of the target path. An arrow
will point toward the location of the cable/pipe in 45-degree steps. A solid line will
appear over the cable/pipe, indicating its orientation to the receiver handle.
For example:
Figure 1:
If the target path is to the right of the
receiver, and running parallel to the operator, the
right arrow will display.
Figure 2:
If the target path is to the left and in front
of the operator (not running parallel to the receiver)
the arrow will point toward the top left side of
the screen.
Figure 3:
When the receiver crosses the target path,
a solid line will appear, instead of arrows, indicating
the target path and its orientation to the receiver
handle.
Before marking target path, always use directional peak or special peak mode to verify
location.
