A
A
A
A
E
E
E
Exxx
xp
p
p
pllllaaa
an
n
n
naaa
attttiiiio
o
o
on
n
n
n o
o
o
offff tttth
h
h
heee
e """"O
O
O
OV
V
V
VE
E
E
ER
R
R
RH
H
H
HE
E
E
EA
A
A
AD
D
D
D"""" R
R
R
Reee
ep
p
p
po
o
o
orrrrtttt
In general the Model
reports OVERHEAD
when it calculates that the field source is closer to
the receiver chassis than it is to the pointer head
In practice in a real world locating situation the
OVERHEAD report can mean several things
Obviously the OVERHEAD report can mean that the line or sonde being
sought is literally overhead with respect to the receiver For example during
an indoor line trace it can mean that the line is actually in the ceiling instead
of the floor If this is the case the user need only swing the receiver
° to
achieve the correct result
The OVERHEAD report could also mean that "competing fields" are present
Competing fields come from sources other than the intended target They
can result from external interference Also they can emanate from lines that
have been unintentionally energized by induction "slopover" In this case
swinging the receiver
° may not result in any improvement to the locating
result
Finally the
Receiver may report OVERHEAD when there simply is not
much signal available with which to work The better the signal strength the
better the receiver is able to perform its job The receiver may have
difficultly making accurate calculations in a low signal situation Also it is
very likely for competing fields to be present in a low signal situation In
such cases the user is encouraged to improve the strength of the transmitter
signal if possible For instance this may be done during a line tracing job by
moving the energizing point closer to the area where the line is being traced
