| Locate
broken wires and shorts in telephone
and data cables within 5cms
Location
of
cable
faults
is
normally
carried
out
in
two
phases.
First
a
location
is
made
from
the
ends
of
the
cable
using
either
bridge
or
pulse
techniques.
The
position
of
the
fault
is
usually
expressed
as
a
percentage
of
cable
length.
A
search
is
then
made
in
the
region
of
the
first
location,
the
Kevin
system
carries
out
the
pinpoint
test.
The
Kevin system comprises two units,
a Cable driver and a receiver/probe.
The
Crystal
controlled
cable
driver
is
connected
to
one
end
of
the
cable.
This
driver
injects
a
10KHz
signal
into
the
cable.
This
frequency
is
chosen
to
allow
long
cable
lengths
to
be
used
whist
still
allowing
sufficient
discrimination.
The
driver
voltage
is
restricted
so
that
the
system
is
safe
to
use.
The
fault
location
probe
is
then
passed
along
the
cable
until
the
signal
strength
drops.
This
is
the
location
of
the
break.
The
signal
can
be
monitored
in
2
ways.
1.
A
1Khz
tone
in
the
headphones
becomes
louder
and
quiter
depending
on
the
strength
of
the
signal.
2.
An
Analogue
meter
(with
adjustable
sensitivity
control)
shows
the
strength
of
the
signal.
The
probe
using
a
tuned
circuit
together
with
crystal
controlled
ring
modulator
mixer,
this
ensures
that
the
probe
will
only
indicate
signals
produced
by
the
cable
driver.
The
probe
is
unaffected
by
mains
signals.
The
system
can
be
used
to
detect
short
circuits
as
well
as
breaks
in
the
cable.
When
using
twisted
pair
cable
the
signal
will
rise
and
fall
periodically,
the
fault
will
be
pinpointed
when
the
signal
strngth
becomes
constant.
Rechargeable
batteries
power
the
system
so
it
can
be
used
even
when
there
is
no
suitable
power
source
available.
Two
battery
chargers
are
supplied
with
the
system,
this
allows
it
to
be
left
on
charge
so
that
it
will
always
be
available
when
you
need
it.
|
Power supply: internal recharargable 12V Battery, charged by
mains powered recharger (included)
