© 2014 Radiodetection Ltd
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To use as a sonde, connect both transmitter leads to
the FlexiTrace stud terminals. As the FlexiTrace
terminals are not color coded it does not matter to which
terminals the leads are connected. To use the
FlexiTrace in line mode, connect the red transmitter
lead to one of the FlexiTrace terminals and connect the
black transmitter lead to a suitable ground connection.
8.6 Stethoscopes
8.6.1 When to use a stethoscope
At times, it may not be possible to put a clamp around a
cable because of congestion or because of
inaccessibility. A stethoscope antenna should be used
in the place of the clamp to identify cables.
8.6.2 How to use a stethoscope
Plug the stethoscope into the locator accessory socket.
Press the concave head against each cable in turn to
detect a maximum signal.
8.6.3 Types of stethoscope
Large stethoscope antenna
The large stethoscope antenna, which plugs into the
locator accessory socket, is used for cable identification
in situations where the cable is exposed. It is particularly
useful for identifying heavy cables lying in a tray where
it is not possible to fit a clamp. The concave detector
head on the end of the insulated, flexible gooseneck is
placed firmly against the cable to be identified. If there
are a number of cables, the stethoscope antenna will
give the strongest response from the cable to which the
transmitter signal has been applied.
Small stethoscope antenna
The small stet
hoscope antenna has a 25mm (2”)
concave head at the end of a 2m (6½ft) lead. The small
stethoscope can be screwed into an extension rod or
used at the end of several extension rods joined
together for identifying inaccessible small cables.
Miniature hi-gain stethoscope
The miniature stethoscope is similar to the small
stethoscope but has no handle or facility for extension
rods.
The miniature stethoscope can also be used as a
miniature antenna for locations where the bulk of the
locator makes it inconvenient for use, such as locating
pipes or cables in walls.
8.7 Submersible antenna
8.7.1 When to use a submersible
antenna
Tracing buried pipes and cables across waterways and
estuaries are frequent and critical locating applications.
Less frequent but equally important is tracing and
locating lines between the mainland and offshore
islands. When locating pipes and cables the locator
sensing antennae should be as close as possible to the
target line, therefore it is not practical to locate lines
buried under a river or seabed from the surface. In most
cases, it is necessary to measure the depth of cover to
ensure the line is protected from dragging anchors or
other underwater hazards.
The submersible, double depth antenna is suitable for
use under water for tracing pipes or cables. There is a
weight at the bottom of the antenna for stability and the
unit has been pressure tested to IP68 to a depth of
100m (300ft).
The antenna is supplied with 10m of submersible
marine umbilical cable as standard, but lengths of up to
100m can be supplied. The extra length enables the
antenna to be carried by a diver on a riverbed or seabed
while the locator is used in a surface vessel. It is crucial
to have effective communication between the operator
with the locator and the diver with the antenna.
Alternatively the antenna can be fastened to the end of
a non-metallic boom from a barge and lowered to the
riverbed or seabed.
8.7.2 How to use a submersible
antenna
Apply the transmitter signal to the target line at an
access point on the shore. The submersible antenna
line for tracing the line underwater is plugged into the
accessory socket of the locator. The locator is used
onboard a boat, which should by positioned directly over
the line. The transmitting signal should be by direct
connection with the strongest possible signal and at the
frequency that the submersible antenna is calibrated at.
Make a ground connection about 50m (160ft) from the
transmitter. Test the quality of signal on the line before
locating on the water.
NOTE: The submersible antenna is calibrated to work at
one frequency.
Tips for using a submersible antenna:
40mm
Figure 8.10: FlexiTrace
8mm
40mm
Summary of Contents for rd7000+
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