THIS IS PART 1 OF BURGULAR ALARM BYPASSING.

Part 1 is an introduction to the various types of alarms in use today.
So we
will discuss the circuits that guard a building’s perimeter.
Therefore, they are used
primarily on doors and windows. The most
common member of this family is the magnetic switch,
the little set of
white rectangular boxes seen above doors of most businesses. RadioShack /> is one business that love to use them because they market them for there
home security
line. Part 2 will deal with second line defense, the area
sensor. These sensors monitor a
specific area rather than a specific
point of entry. These are often called motion detectors,
sinnce anyone
moving about a guarded room will be detected.(like no shit!) The way in

which these sensors achieve this goal varies between components. And in
Part 3 I will give you
some general notes and observations on alarm
bypassing.

1.0 MAGNETIC CONTACT
SWITCHES

The magnetic switch is the most common of all hardwired components found

on doors and windows around the world. It consits of two individual pieces,
the switch itself,
and the companion magnet (see Fig 1-1). The switching
mechanism is a spring loaded lever that
makes contact with a stationary
metal arm when the companion magnet is near. So the magnetic
switch is a
normally closed circuit. When the magnet is pulled away (see Fig 1-2), the

lever is released from the stationary arm and the circuit is no longer
complete. So, the
opening of aprotected door or window removes the magnet
from the switch, and since the circuit
is no longer complete the alarm
sounds (simple electronics!!). Since the circuit of a magnetic
contact
switch in normally closed wires cannot be cut to defeat the system cause
this
has the same effect as removing the companion magnet.
The magnetic switch offers more
opertunity for jumpering than does any
other individual component. since the wires are often
visible, one only
needs to remove the insulation, and place a small wire across the circuit /> to defeat and bypass the switching mechanism (fig. 1-3). The main problem
for the thief
then is to locate the wires if they are not visible. Often
they are hidden behind baseboards
or trimming or are snaked through the
studs behind the drywall. They may be uncovered from the
outside after
the bricks and wallboard have been removed.

Figure 1-1 Figure
1-2
Closed Switch Open Switch
I II I I II I
I II I I II I

I(——)II(——-)I I(——–)II(——-)I
> I(…../)II( + )I I(:……/)II( M )I

=======@@: / )II( )I =======@@: / )II( I M )I
I( / )II( ### )I I( / )II( S A )I
I(
/–:)II( ### )I I( / )II( S G )I
< I( II( ### <—MAGNET I( -:)II( I N )I

========@@: II( ### )I =======@@: ^ II( N E )I
I( :::::)II( ### )I I( …|..:)II( G T
)I
I(——)II( ### )I i( —|—)II(——–)I
I II( )I |
I II( + )I Connection
broken
Because of missing magnet
so the alarm sounds!!!!!!

Figure 1-3

I II I
I II I
=============*==@ II I
* I II I
* I II I

=============*==@ II I
I II I
^
|_ Jumper Wire

Usually one has to
already be inside to get at the wires however ther are
a few tricks that burglars employ.
Often a hole can be drilled into the
window and jumpering is done if the wires are visible.
One way to make the
wires visible is to unscrew the switch and give it a little pull. The
wires
will probably be stapled and may be difficult to pull, but there is a
chance that
the wires are just stuffed in between the studs. This is done
carfully so the switch is not
removed too far from the magnet. Also if
possible the magnet may be unscrewed from the window
itself and taped to
the switch (It was done to a Radio Shack!). The door or window could
then
be freely opened.

1.1 Window Foiling

Window foiling is
probly the alarm which everyone is familiar with. It
graces the windows of nearly every store
in America, and rightfully so, it
is very difficuly to bypass successfully BUT NOT
IMPOSSIBLE!
When a window is to be monitored by foil the foil is stretched around the

perimeter of the window. Two terminals are placed at the end of the foiling
and are connected
to the rest of the circuit. The foil is now part of a
normalclosed circuit, its so fine that
if a break occurs in the glass, the
foil will tear, opening the circuit and causing the alarm
to ring.
Foiling is often coupled with magnetic switches and there lies the big
problem
for the burglar. If he cannot break the window how can he/she
enter? There are three primary
methods that burglars employ when defeating
window foil. Amateurs on the other hand who dont
fully understand the
principles of window foil cicuit try some crude methods that are
usually
unsuccessful. They sometimes smash a window and hope that the foil won’t
break
as well. The odds of this happening are astronomical, they better
try playing lotto! Amateurs
even try cutting the entire window out since it
allows them to get access to the jumper
terminals. But any slight movement
in the wrong direction sets off the alarm (while they’re
holding a 20
pound sheet of glass).
One method that will work provided the window is
large enough (or the
burglar is small enough) is the cutting of a crawl space in the window
that
is far enough from the foil so it can be undisturbed. The entire window
is covered
with a strong duct tape, leaving blank the hole intended to be
cut. The hole preferbaly
square, is scribed with a high quality diamond
tipped glass cutter. The cutter is then used to
trace and retrace the
scribbed line until the glass get quite thin. When the lines have
been
determined to be deep enough, a thin layer of modelling clay is applied
to the
glass area that is to be removed. Then a thick wet newspaper
(to shield the noise) is laid
over the potential hole and tapped sharply
around the scribbed lines. With practice the glass
will break only where the
lines were cut. The duct tape serves as a shock-absorber, and also
keeps
the plass from shattering and falling to the floor if a mistake is made.
The layer
of clay serves to deaden the sound of the glass as it hits the
floor inside.
Another
method often often used is the jumpering of the two foil terminals
If they are visible a small
hole is drilled into the glass near them
(when drillin glass always use a carbide bit). A wire
is then laid across
the terminals to completely bypass the whole foiling system. The wire
is
then fasten securly to the terminals to avoid having it fall off during the
mission.
At anyrate if jumpering is successfully accomplished, the entire
pane of glass can be
shattered without setting off an alarm.
The third method is utilized when one has prior access
to the premises.
When no one is looking use a razor blade to slice a line thruogh the foil. /> The slice is clean enough to so it can’t been seen easily but also deep
enough to the the
circuit is not intact. When the store owner decides to
arm the alarm (turn-on) he’ll discover
that the zone zone covering the
window is not properly armed. After a quick survey of all the
window foil
he figures that the system must have malfunction and decides to call the

repairman first thing in the morning. If this occurs the window containing
the cut foil will
remain unguarded all night. It is possible that the owner
could call a repairman that instant,
but AN INTELLIGENT burglar will be
keeping his/her eyes out for that. If the owner finds the
tear there really
nothing much he can do without the proper tool and supplies. From the

burglar’s vantage point he/she could be able to see any repairs the owner
is making on a
particular window and act accordingly.
NO, window foiling is not particulary easy to bypass,
but remember it is
not necessary that the burglar enter through a window either. They know /> that a window that has just been cut is not a pleasant thing to crawl
through, and it’s not
terribly wise place to be seen crawling. A large
hole cut in a windoew just has
"BURGLARY" written all over it for any
passer-by.
Well I’ve given you the
basic and there is more to encounter so look
for .

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