14
Searching
Areas
along
a
Chain
Link
Fence
Searching
in
the
vicinity
of
a
chain
link
fence
requires
a
reduced
sensitivity
setting
and
some
control
over
the
orientation
of
the
locator.
As
illustrated
in
Figure
22,
position
the
locator
horizontally
with
its
long
axis
perpendicular
to
the
fence.
This
insures
that
the
upper
sensor
is
kept
away
from
the
fence.
Figure
22:
Searching
in
the
Vicinity
of
a
Chain
Link
Fence
Perform
the
search
by
slowly
moving
the
locator
forward
along
the
fence
while
also
moving
it
to
the
right
and
to
the
left.
As
you
move
forward,
this
technique
allows
you
to
search
an
area
several
feet
wide.
Listen
for
an
abrupt
drop
in
the
signal
(as
shown
by
the
null
in
Figure
23)
that
will
occur
when
the
lower
sensor,
located
1
‐
1/2
inches
from
the
end
of
the
locator,
is
directly
over
the
stake.
Any
variation
in
the
position
of
the
locator
will
produce
an
abrupt
rise
in
the
frequency
of
the
signal.
Figure
23:
Abrupt
Drop
of
Signal
while
Searching
along
a
Chain
Link
Fence
Locating
Valve
Boxes
Both
the
valve
and
its
casing,
when
iron,
provide
strong
magnetic
fields
that
make
them
easy
to
locate.
Plastic
enclosures
containing
magnets
(which
are
typically
used
with
non
‐
ferrous
valve
boxes)
are
easily
located
at
depths
of
6
feet
or
more.
Figure
24:
Locating
Valve
Boxes
and
Casings
Summary of Contents for GA-92 XTd
Page 20: ...20 SECTION X PARTS DIAGRAM ...
