
2
MAXIMUM METHOD
With the instrument turned on, push the peak-null switch to the peak position. Hold
the instrument with the receiving antenna close to the ground and right angles to the
direction of the cable.
Adjust the sensitivity control up ( clockwise ) until an on scale meter reading is
found. Walk in the direction that increases the meter reading. The meter will
increase as you near the cable. If the meter goes off scale, decrease the sensitivity
control for an on scale meter reading and continue to walk in that direction. At
some point, the meter will start to decrease. Stop at the location where the highest
meter reading was found. Rotate the instrument to the right and then to the left.
When the highest meter reading has been found by rotating the instrument and by
moving it side ways back and forth. The antenna is pointing at the cable and the
instrument handle is in-line with the direction of the cable route.
Now that the cable has been located, the cable path can easily be traced. With the
antenna directly over and at right angles to the cable path, walk in the direction to
be traced. Keep moving the instrument from one side to the other and each time a
maximum reading is found, the cable will be directly below the receiving antenna.
The loudspeaker audio will respond the same way the meter responds to the signal
level. The maximum audio will be heard when the meter is reading its highest point.
When the cable has been found and the exact position is needed, turn down the
sensitivity control until a very small movement of the meter can be seen as the
antenna passes over the cable (the lowest reading the operator can detect on the
meter). This will help insure other cables in the area are not inuencing the
location.
NULL
See Fig. 2
The receiver will see a high signal on both sides of the cable and a loss or minimum
signal directly over the cable. Unlike the peak method, in the null mode the
instrument is unidirectional and will not provide direction to the cable route. The
instrument antenna can be at any angle to the cable route and it will see the same
signal level.
NULL METHOD
With the instrument turned on, push the null-peak switch to the null position. As
the instrument is moved toward the cable, the signal level on the meter will increase.
As the receiving antenna crosses the cable, the signal level will drop to a very low