Operating instructions
9b.
To
analyse
the
find:
a rejected object
will
give a swing
to
the
left
on
the
meter and a
decrease in
audio
response; a
worthwhile
target
will
give a swing
to
the
right
on
the
meter and
an
increase in audio response.
10b. The Discriminate Level may be fine tuned in each
of
the
three main D modes
by
varying the Discriminate level
control.
11b. The Sensitivity Level may be varied
but
0
is
the
recommended level
in
the
Analytical
Mode.
OPERATING
IN
THE
DISCRIMINATE
MODE
On a
wet
salt beach
it
is
best
to
operate in a Discriminate Mode all
the
time.
This
is
because
the
salt
water makes
the
ground conductive. and
to
ground exclude
in
these
conditions
the
detector
needs
to
be set at a
point
where
iron
is
rejected.
This
is
a useful coincidence because
it
means
that
ground
exclusion and
discrimination
against iron are possible at
the
same
setting on
wet
salt
sand
with
the
1200-8. The ground exclude setting
for
beaches
is
not
as
exact
as
that
for
inland siles and in practice
it
is
possible
to
reject silver paper and ground exclude
on
a beach.
D2
or
D1
are
the
recommended
mode settings.
The
qiscriminate
level can also be adjusted
to
suit
the
particular conditions.
Follow
Steps
1ยท3
"Setting
the
Tuning
Level
of
the
Detector."
4c.
Lower
the
search head
to
the
ground. Keep
it
at a steady height above
the
ground and
p.nsure
the
tuning
level
is
set
correctly
by
operating
the
ADC
switch
to
the
left
or
right
and
then
release it.
5c.
To
operate in a Discriminate Mode set the
Function
Control
to
the
relevant D level.
and
then
press
the
ADC
switch
to
the
right
and then release
it.
6c. The
Sensitivity
Level may be varied. On a beach
+5
is
recommended.
If.
however.
the
detector
is
being operated in
the
Discriminate Modes
on
an
inland site.
it
will
be
necessary
to
balance the Sensitivity Level
to
reduce
the
ground effect. I n practice
th
is
means setting
it
to
the highest level possible.
which
will
of
course depend on
the
degree
of
mineralisation. and
how
capable
the
operator
is
at
keeping the search head level
with
the ground. A sacrifice
in
Sensitivity Level
will
drastically reduce the ground
effect.
but
will
not
reduce
the
depth
penetration
to
the
sam~
degree.
For
example,
by
reducing
the
SensitiVity level
from
+5
to
O.
ground
effect
willl:)e
reduced
by
800%,
but
depth
penetration
will
only
be reduced
by
about
20%.
USE
IN
THE
FIELD
~~~
Detection
Area
X
\~
TR
detectors
employ
a
Total
Response search
Search Are
_.~
head
which
means
that
the
object
can
be
detected across
the
full
width
of
the
search
head.
~
r--
--_____....
_____
l Diagram
3.
. -
Detection
Range
Detection
ranges
will
vary depending on the
size
of
the
object,
the
length
of
time
an
object
has
been
buried. and the
type
of
ground the object
is
buried in. The best ground conditions are
dry
well
compacted soils then coins can be
found
at the greatest depths
if
they
have been buried
for
some
time
and
the
coin
has
interacted
with
the salts in
the
nround,
thereby
appearing larger
to
the detector.
The
worst
conditions
for
detecting are on loosely compacted
or
freshly dug ground
or
when
the
object
has
only
recently been buried. In these
conditions
detection
range
will
be reduced. 90%
of
all objects
are
found
within
6"
of
the
surface. Adverse soil
conditions
can reduce
depth
of
detection
by
more
than half.
Determir,ing the Target Size
and
Depth
An
operator
who
is
familiar
with
his
instrument
will
be able
to
do
an
excellent
job
of
determining
object size,shape and
depth
before he digs. The technique
is
learned
from
careful analysis
of
the audio
signals coming
from
the
detector. Each
time
a signal
i,;
heard, listen
for
any peculiar characteristics
it
may have; determine over
how
large
an
area
you
get a
detector
signal; and
try
to
'outline'
the object
before
you
dig. Listen
for
the
sharpness
or
dullness
of
the
signals and determine
the
magnitude
of
strength
of
the signal. A
coin
will
have a sharp signal, 3 nail a
fuzzy
signal.
CARE
AND
MAINTENANCE
Care
of Your Detector
The
working
life
of
your
detector
will
be shortened
by
careless
use
or
neglect
of
the
unit.
Think
of
your
detector
as
a scientific
instrument
NOT
A
TOY.
Your
detector
is
designed
to
withstand
rLogged
handling on any terrain,
but
mis-use
or
lack
of
due
attention
will
tell in the end. -
II
7