User manual

RD7000+ Operation Manual 13
Figure 4.2: Pinpointing a target line
4.3 Trace
Line tracing can be accelerated by switching the locator to
null response.
Move the locator left and right while walking along the
path of the line to observe the null directly over the line and
a peak response to each side of the line. As you move
the locator over the line, the left and right arrows (and an
accompanying tone) will indicate if the target line is to the
left or right of the locator.
Periodically switch to peak mode, locate the target line,
and verify its exact position.
Figure 4.1 Line tracing
4.4 Pinpoint
Pinpointing a target line in peak mode, denes the exact
position of a target line after it has been traced and its
position is approximately known. Start with medium
output power from the transmitter, medium frequency
on the transmitter and locator, and peak mode on the
locator.
Set the locator sensitivity to approximately 50%.
NOTE: it may be necessary to adjust the sensitivity level
throughout the pinpointing to keep the bar graph on
scale.
Peak
mode
Null
mode
True
Position
Peak
Position
Null
Position
Figure 4.3: Pinpointing with Peak/Null
1. With the antenna perpendicular to the line, make
traverses across the line. Dene the point of maximum
response.
2. Without moving the locator, turn it round as if it is on a
pivot. Stop at the point of maximum response.
3. Hold the locator vertical with the antenna just above
the ground and move the locator from side to side
across the line. Stop at the point of maximum
response.
4. With the end of the antenna close to the ground,
repeat steps 2 and 3.
5. Mark the position and direction of the line.
Repeat the steps of the procedure to increase pinpoint
accuracy.