339 lines
18 KiB
Plaintext
339 lines
18 KiB
Plaintext
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=The Science of Telephone Surveilance=
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= Brought to you by Eric The Red =
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======================================
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Wiretapping
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The Telephone is always a favorite target for the potential spy as it provides
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access to a capsule summary of many important decisions and transactions. It
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also offers a number of easy tap-in points which may not even necessitate
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premise trespass, and are generally harder to discover.
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Numerous devices have been marketed by professional bugging suppliers to tap
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the telephone, and in some cases, even utilize the telephone as a room bug when
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not transmitting phone conversations.
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Literally thousands of there devices which could be installed by almost anyone,
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were sold prior to the great surveilance scare laws. Access to commercial
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devices of this type is now pretty much limited to law enforcement bodies,
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although there is an undeniable blackmarket for "radio repaiman specials".
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Common "conference line broadcasters" sold for as little as $30 for the schlock
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"private eye" suppliers in th late 60's, while a top law enforcement
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counterpart brings a couple of hundred bills from the more viably financed
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police and investigative departments.
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The state of the art is such in wiretapping that it is possible to buy (or
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build) such exotic taps as the microphone which drops into the handset of a
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phone in as long of a time it takes to unscrew the cap, looks identical to the
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regular microphone, and broadcasts both sides of the conversation (using the
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phone's own electrical power) to a nearby FM radio.
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Another popular exotic is the "infinity transmitter"; a small, cube-shaped
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device which hooks into the phone and jst lies there, hibernating, one might
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say, until the phone is dialed from an outside line (anywhere in the world - as
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long as it is direct dialing) and a small whistle blown into the mouthpiece of
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the dialing phone.
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Upon "hearing" this sound the infinity transmitter stops the parent phone from
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ringing, and turns on the phones own carbon microphone or uses its own to
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broadcast the room's sounds over the phone line to the listening whistle-
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blower.
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This device was popular (for those of us who had $400 dollars to blow on such
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things) gimmick for traveling businessmen who had an extension phone in the
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bedroom where their wife slept...A quick call from any port would let the
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listener know exactly what was transpiring in his absence.
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In phone tapping, much as in most forms of surveilance, the key is the same:
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Keep it simple and direct. The less complicated a system, the better the chance
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of success.
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Direct Taps
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Phone tapping falls into two general categories; direct, meaning an actual
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electrical contact from the phone or line, to the listening post, or wireless,
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this latter being a combination of a phone tap and a mini-transmitter.
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Direct taps are the easiest, and often the best. The quickest method of tapping
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into a phone is simply to locate a good point along the phone line, strip away
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the insulating cable to expose the four enclosed wires, strip away a small
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piece of insulation on the two hot (red and green) wires WITHOUT CUTTING THE
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WIRES, and attach a set of high impedence headphones. One side of the phones is
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directed through a small .005 mfd capacitor to keep out the 48 volt phone
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power.
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With this simple set-up. the bugger has to go listen to the headphones whevever
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a call is made on the instrument in question. The disadvantages tp this system
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include spending most of one's time waiting for the phone to be used and then
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rushing to the garage every time it happens...It is often difficult to explain
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one's presence when discovered in such situations.
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The next logical step up the ladder of progressive involvement is to add a
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small inter-satge transformer along with the capacitor. The primary of the
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transformer should be at least 10,000 ohms (but not over 20,000) to match the
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phone lines' high impedence, the secondary should be of a near value to the
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equipment it is going into.
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This set-up provides a clear passageway for the audio (conversation) to pass
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through, while not loading the phone line. This "not-loading" is a real factor
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to consider, as a draw of over 20 mills or so might trip the central exchanges
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relay (trips around 40 milliamps) and send a phone repairman scurrying to the
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scene of the crime.
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This output can be fed directly into a tape recorder, eliminating the
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crouching-at-the-phone syndrome. However, one must still endeavor to turn the
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recorder on and off at the proper moments, as task sometimes easier said than
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done.
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To eliminate this final problem, one adds a tiny bit of sophistication; the
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drop-out relay. This is a small device that senses the condition of the phone
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line in question, and, through the remote start feature found on most modern
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tape recorders, turns the recorder on when the phone is lifted off of its
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cradle. This, of course, limits the waste of tape, and needs attention only
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when necessary to turn over or install more tape.
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Another, more esoteric value of this set-up is the fact that it is probably the
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kind of thing used to tape record all the calls made out of the White House.
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Now, this in no way reflects on the quality of quality of the recordings
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obtained, with a bit of care one would not find any unexplained gaps in the
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tape...
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It is possible to employ any of these methods at any point along the "pair",
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either as it leaves the phone, before the surge protector, on the drop cable
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running to the telephone pole, or at the terminal or junction boxes located on
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the pole or in the building's garage or basement.
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The telephone instrument itself can be used as a microphone by any number of
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simple alterations (the addition of the infinity transmitter being the most
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common). Any of these alterations will allow the+;;+F{FK#+sF{&{{kkconversation when the phone is on the hook. To use either of these alterations,
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the bugger simply connects a sensitive amplifier anywhere on the phone line.
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1) The most common is to place a resistor across the hookswitch (this is the
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switch activated by the placing of the phone on its cradle). The resistor must
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be fairly low as to not throw the trip relay in the central station. This
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set-up allows a bit of current to trickle through the microphone and activate
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it, sending the conversation down the line much as an ordinary phone call will
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do, albeit at a lower level.
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2) A capacitor can be installed across one side of the hookswitch allowing a
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bit of audio to pass on by, but keeping the DC current where it belongs.
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In both of these applications, one side of the double pole hookswitch must be
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shorted out, leaving the open side to accept your device.
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Near Direct
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There is one other form of almost direct tap - the induction pick-up. These can
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be commercially purchased in electronics shops for a couple of bucks and are
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designed to be fed into a home tape recorder. They have a few important
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limitations? they must be physically attached to the phone, usually near the
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base or sidetone coil, to work properly, and also the volume level is not the
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best, and they are subject to AC hum from nearby electric devices.
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A way around some of these limitations is to hide the induction coil in some
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little object (desk blotter, pen set, etc.) that may be placed near the phone,
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and then employ a small, direct-coupled amplifier to beef up the weak signals.
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In this manner, the induction pick-up becomes a bit more practical as it and
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the amplifier (and in some cases, the tape recorder) can be concealed in a
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drawer under the phone, or in a nearby artifact.
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Commercial hidden induction units are sold by the usual law enforcement
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suppliers cleverly secreted in such things as fake flowers (which only
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reinforces my dislike for plastic flowers), desk blotters, picture frames, etc.
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Most induction pick-ups have a small suction cup attached to make it easy to
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attach to the phone. Many pick-ups will even work on an extension phone even if
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though the extension phone is still lying peacefully on its cradle.
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It is also possible to use a powerful induction tap near the phone line, but a
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real beefy amp must be employed and this sort of thing never works out quite
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like the spy movies would have us believe: be practical, stick to direct routes
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when possible.
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A real classy method is to put the induction pickup INSIDE the phone, and have
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its leads run to the two unused (black and yellow) wires, where the bugger can
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use a normal bug to these two wires (but only in parallel) without ever making
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any contact with the main line.
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Wireless
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--------
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The other approach of the problem of not knowing what is said over your
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neighbor's phone is to secrete a small transmitter in the phone, or along the
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line, which broadcasts the conversation to a nearby reciever/tape recorder.
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Telephone Tap Detection
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-----------------------
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Only the most amateurish wiretapper would betray his (or her) presence by
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producing spurious noises, i.e., "clicks" on a telephone line while in use.
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Most line noise is a naturally occurring phenomenon which does not indicate the
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presence of a third party on the conversation.
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Therefore, bug fighting requires more than a mere surface understanding of the
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game. To begin the process, one should have more than a passing grasp of the
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dear old telephone company itself.
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Telephone exchanges use a 48-volt DC power to operate their equipment. The
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phone is rung by inserting an AC ringing of about 20 cycles. The central telco
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office contains a series of frames wherein each subscriber's wires are attached
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to a set of contacts and a system of relays.
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Your instrument is basically a microphone/earphone combination, a bell, a large
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coil (near the base of the phone) known as a sidetone coil, and a relay.
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When the phone is on the hook, this relay is open. When you lift the reciever
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up from its cradle, the relay contacts are closed (in effect you are just
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closing a switch). When you dial, this relay is opened and closed a number of
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times (on a rotary phone). The central relay reads this series of openings and
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closings and then connects you to the proper set of contacts to reach the
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number you are dialing. On a tone phone, the tones sent down the line are
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decoded by the central office and you are hooked up.
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When your wire leaves the main office, it is in a cable containing many similar
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wires, or "pairs" (it takes two wires for every phone). This cable comes to
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your pole where it goes into a junction box, and then to your house or
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apartment. When the pair reaches your residence, it comes to a device known as
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a surge protector. At this surge protector a third wire is added. This third
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wire is in the middle of the other two and is the ground wire.
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From the surge protector the three wires (and sometimes a fourth, non-used one)
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run into your telephone. A number of bugging devices can be utilized in just
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about any of the aforementioned areas to record and/or transmit your phone
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conversations, and sometimes even just room conversations.
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Types of Bugs
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One of the most common types of bugs for the teley is the line powered parallel
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bug. This type of bug draws its power directly from the line and radiates a
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constant signal, whether the phone is in use or not. Its major advantage is
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lack of batteries (it can conceivably run for years). Its major disadvantages
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are: the constant signal makes it easier to detect, and the current it draws
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can often be measured.
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This unit can be installed anywhere on the phone line (even on the pole) or in
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the phone itself. Although the in-the-phone mounting is considerably harder to
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effect due to limited access, it has the advantage of only operating when the
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phone is in use.
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This type of bug can also be battery powered. This means a better range, and
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less chance of detection, but a much shorter life, or battery replacement at
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selected intervals.
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A series bug is even more common. This unit requires the installer to actually
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cut the phone wire (rather than just attaching as in a parallel bug) and
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install the unit, but it only works when the phone is in use, and does not load
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the phone line at all when the phone is not in use, meaning the chances of the
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phone company detecting it are considerably smaller.
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By utilizing a phone induction pickup (purchased at tape recorder stores for a
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couple of bucks) a bugger can actually tap a phone without any installation
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other than proper placement. The problems here are that the pick-up should be
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placed near the side tone of the phone itself (or an extension phone) and the
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output must be amplified before recording or transmitting. This type of tap is
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alos much more likely to pick up hum and generally be hard to understand.
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The commonest method of phone tapping is to simply connect a set of high
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impedence headphones through a capacitor onto the phone lines, or add a small
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matching transformer and go right into a tape recorder. This set up will record
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both sides with amazing clarity. If a drop-out relay is added (or a voice
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operated relay such as a VOX) to the tape recorder, it will only operate when a
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call is being made, thereby conserving tape and power.
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There are a number of things one can do to help eliminate the chances of phone
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conversations being overheard by outside parties. These range from the simple,
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and as one might excpect, up through the very complicated. The chances of
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detection increase with the complexity, BUT if the bug is a fairly amateurish
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(non-FBI, that is to say) job, a few simple approaces will probably turn it up.
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Phone Company
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The Phone Company will help to some degree (assuming they are ot the ones doing
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the bugging - Ma Bell has done more than her share of this sort of thing,
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either for her own records or by leasing equipment and lines to law enforcement
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agencies...)
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If a bug draws more than 40 milliamps of current it will automatically trip the
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central office relay, alerting Ma to some problem which needs the attention of
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a repairman, however, no pro or even semi-pro is going to install anything that
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will eat up this kind of power. You can call the phone company and ask them to
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run a check on your line for possible bugging and they will run a current check
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(anything over a 1 milliamp loss makes them suspicious) and listen for hum,
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unusual crosstalk, or other alarming symptoms. A simple check like this will
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often do the job...and best of all, it's free.
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Telephone company will often also dispatch a special investigator to check out
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the line in person. If a tap is dicovered, the telco will remove it, restoring
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the customer's privacy, but will not help in finding, or the possible
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prosecution or the tapper(s).
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If the tap does not tresspass on telco property (i.e. and inductive tap) they
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might not even wish to remove it, but will show it to you or refer you to local
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law enforcement bodies, assuming LOCAL LAW ENFORCEMENT BODIES DID NOT PLACE THE
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TAP...THE PHONE COMPANY WILL NOT FINK ON ITSELF OR LEGAL, "AUTHORIZED"
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AGENCIES...
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Whether you elect to utilize the services of the friendly phone company or not,
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you should also plan on a self-search. This is done by examining the phone and
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its wires with a deft hand. Start with the wires...
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Trace your phone wire to its wall plug and then from there throughout the
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basement, or wherever to the surge protector. See another little wire attached
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along the way and running into boxes or cabinets? Anything placed against the
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wire that could be a tap? Check out your "pair" into the junction box if
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possible (this is especially easy if you live in an apartment where the
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junction box can be quickly located). Any funny little wires or little gizmos
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hooked onto your pair?
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Countermeasures
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---------------
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If you suspect you are the victim of an unauthorized telephone surveilance
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campaign, there are a few things you can do to lower your risks:
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Keep your phone(s) locked up in a drawer when not in use and deny access to
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your premises to anyone, including cleaning people, without your constant
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surveilance. Always check any "repairman" and call to verify it with the phone
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(or gas - whatever) company.
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Limit your non-critical calls to one phone and occasionally, only when it's
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important, use another phone on another line. However, if you make a habit out
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of this sort of thing, the other phone will get the same treatment. EvenKkphones have been bugged near a subject's house or place of business by over-
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zealous spies or law enforcement types.
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You can use a commercial scrambler; these devices emply several methods to make
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the human voice sound unintelligible to anyone not equipped with with a like
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device. They have the advantage of screwing up all eavesdropping, including
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switchboard operators and chance listeners, HOWEVER, cheap scramblers simply
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remove a sideband of the conversation, or insert the speech patterns which can
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be defeated with a simple device and even expensive $500-a-set jobs can be
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defeated by anyone with the time and equipment to crack the scrambling code.
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Largy spy outfits (i.e. governments) employ computers to figure out the code
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and descramble with only minor hassle...
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You can feed some sort of noise (radio would work fine...) into the phone when
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not in use if you feel the conversation is being recorded. This will actuate
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any voice operated or line-tripped tape recorders and cause them to waste their
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precious tape recording the top 40. This is especially good with the mini-jobs
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which can deal effectively with a maximum of 45 minutes worth of recording
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before the tape has to be serviced.
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It is also possible to mess up a tape recorder by inserting some sort of
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blanket noise into th phone along with your voice. the poor quality mics and
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earpieces used in the telephone itself will not respond to much over 3,500
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cycles per second, while tape recorders will often respond to 10,000 to 15,000
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cycles with ease. If you take your trusty signal generator and feed a sine wave
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of about 8,000 or 9,000 cycles into the line (by direct connection) along with
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your voice (at, say 10 volts or so) it will often completely overload the tape
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recorder and saturate it with the tone, but still allow you to understand the
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person over the phone... This is best employed only at critical moments, not
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during whole conversations, to give the bugger less time to figure out what is
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going on.
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However, the only real, sure countermeasure is not to say important things
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over the telephone.
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Loose lips sink ships...
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Downloaded From P-80 Systems 304-744-2253 * Since 1980 *
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