receiver is DIRECTLY over the cable. If you are a little to the left or
right, the signal will be loud, but DIRECTLY pointing the receiver at
the wire produces virtually no signal. See Figure 3 below for an
illustration of the Null principle. In this way, the user will know the
exact location of the wire or cable being traced. Once the null signal
is acquired, continue to follow the path of the wire by waving the
receiver back and forth across the wire path.
Note: If the volume control is too high, this will overpower the null
signal. If you are not getting a null directly over the wire, try turning
the volume control down.
Figure 3
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