What is surveillance in electronics?
Read the following to find out:
lies and electronics
Everyday Practical Electronics
The police and security services have an armoury of high tech surveillance equipment. Needless to say they do not like to talk about it. Thermal imaging cameras, which find bodies trapped in rubble after an earthquake or bomb blast, can also monitor movement in a dark room. If a laser is beamed at a window, the reflected light will be modulated by the small vibrations in the glass pane which are caused by speech in the room. The modulations are converted back into speech by a device like the readout head of a laser disc player.
All British Telecom`s telephone exchanges are now fully digital. Speech passes through them as digital code and is switched by a computer. This is how BT can now offer its subscribers new services, such as itemised billing, call re-routing and conference calls where several parties are on the line at the same time. The same technology lets BT help the authorities trace the destination and origin of any call immediately it is placed, and tap into a conversation without the tell-tale clicks which often gave the game away on an analogue line.
Amateur eavesdroppers can now work almost as effectively as the professionals. A wide range of devices can either be bought over the counter, or by mail order, or be constructed by an electronic enthusiast.
Once you know what is on sale, you realise how easy it is to be bugged without realising it. Like Gene Hackman in the movie The Conversation, anyone with business or personal secrets can then become paranoic, especially if they understand the technology, and know what is on sale at surprisingly low prices.
Why is that van parked down the road in the street? Who is hidden in the back, with what equipment? Is the aerial on the roof picking up a music radio station, or is it receiving signals transmitted from a bug?Who is that out there in the garden at night? Why are they peering through a stubby looking telescope?.
For legal reasons, of which more later, we can only give general pointers to what is on sale. They are intended to alert the unwary, while not providing too much help for the would-be eavesdropper.
Phone and fax tapping
An ordinary telephone may not be as innocent as it looks. There is no visible sign of tampering, inside or out, but it is recording everything said when a call is made. A small tape recorder, the size of packet of cigarettes, is connected to a telephone extension socket in another room, or to the junction box in the cellar, or outside on the wall.
The recorder costs only around £50. It uses miniature cassettes of the type intended for dictation, but runs them at one-half or one-third normal speed to record several hours on a single tape. The recorder has a sensor, which starts the tape running whenever the handset of any telephone on the house line is lifted. The tape stops running when the handset is replaced.
The telephone junction box also contains a miniature radio transmitter which runs off long-life batteries. It may transmit on the same VHF band that is used for FM broadcasting, so the signals can be picked up by any domestic portable radio, for instance in a car outside the house. Or it may work at higher frequencies, in the VHF band allocated to aircraft, or in the UHF band reserved for lorry fleets, so that the transmissions can only be picked up on a matching receiver. The transmitter costs anything from £50 to several hundred pounds, depending on its power and range.
Perhaps the junction box which serves the Fax machine contains an even more sinister device, bought by mail order from a supplier in Frankfurt, Germany, for DM 8500. Whenever a fax call is made or taken, the "Telefax Interception System" transmits the warble tones that the fax machines exchange. These warbles are picked up by a VHF receiver outside the house.
The receiver triggers a high fidelity tape recorder which captures the full frequency range of the rapidly changing warbles. Later the tape is replayed into a personal computer loaded with a software program which displays the text of the fax on screen. The PC either stores the text on floppy disc or prints it onto paper. The device, says the company, "fits into a briefcase" and can be used in a "parked car in a nearby street". "We have them in stock" confirms the sales representative.
Your cordless phone was bought from a reputable electronics dealer for under £100. It is wholly legitimate and has not been tampered with. But by a quirk of design and government licence it also functions as a surveillance device. A base station plugs into the telephone wall socket and broadcasts speech to a handset which the owner carries round the house or garden. Some of the frequencies allocated by the UK government are at the extreme end of the AM Medium Wave band. So a portable AM radio will often be able to pick up the conversation. If the house is high on a hill, the signals may travel several kilometres.
Even without tampering, an ordinary telephone can release secrets to a caller. Unless you know how, and remember to take positive blocking steps every time you dial a number, your own number is transmitted down the line ahead of the ringing tone.
The system, called Calling Line Identification, is well-intentioned. It can curb malicious and obscene calls. But anyone who uses their own phone to make a call, e.g. in response to an advertisement, immediately makes the called party a present of their telephone number - even if it is ex-directory.
For just £50 (plus a small quarterly service fee), high street shops quite legitimately sell a CLI display device which - also quite legitimately - plugs into any phone line and automatically stores the last fifty numbers that have called it.
There is even a way of using CLI for free, and with no extra equipment needed. Using an ordinary phone, dial 1471 and hear a recorded announcement of the last number that called that phone line.
Camera and sender
Behind a ventilation grille, or hidden inside the smoke detector, burglar alarm sensor, hifi loudspeaker or clock, there may well be a miniature video camera with a wide angle lens that is watching everything in the room. The camera connects either to a TV set, VCR or a device called a Videosender.
Use of the sender is illegal but it is easily purchased by mail order. Its intended use is to broadcast the output of a VCR or satellite receiver round the house, to avoid the need to lay extension wiring, but it can equally well transmit the signal from a camera.
Because the Videosender works on the ordinary UHF TV band, but can be tuned to a frequency well away from the BBC, ITV or Channel 4, its signals can be received on an ordinary TV set or VCR. Sensitive cameras, which work even in low light, cost under £200. Videosenders cost as little as £20, with more powerful models that reach down the street still costing less than £40.
An infra-red video camera can see in the dark. These are sold legitimately, e.g. for watching over babies at night. A lamp bathes the area in infra-red light. The camera uses the infra-red to form an image as if the room were well-lit. Some ordinary video camcorders will respond to infra-red. Ex-military infrared "Dragon" lamps cost over £500, but have a filter which cuts out all visible light so that subjects do not know they are being lit up by a powerful infra-red beam.
Your home or office computer is stylish because it is made of plastic. So there is no metal screening to stop its circuits radiating an electronic imprint of whatever text the computer is displaying on screen. Put a portable radio near a computer and you will hear the radiation as nuisance interference. Enough radiation will leak through the windows to reach a sensitive receiver outside. An oscillator can make it display the stolen text.
The military and security services know this only too well. This is why they use computers which are housed in metal boxes which look ugly but trap radiation. The windows in their offices are also coated with a thin metal film, similar to that used to keep out the sun`s rays. It also keeps in the computers` radiation.
A pen laying on the table, an ashtray or calculator; they can all house a hidden microphone and miniature transmitter. So can a multi-way adaptor plugged into the mains socket in the wall. The socket itself is a risk. It can contain a microphone and radio transmitter. The transmitter is powerful, and transmits over a longer range, because it can draw mains power. So the receiver can be hidden well away from the room. Prices start at around £60.
Ex-military "night vision" gunsights and monoculars can now be bought for £200. For an extra £100 you can get one that will clamp to a camera. Many come from Russia where the army factories are happy for any new market. One dealer alone says he has been selling several hundred a year. He boasts that his "black market goods are carefully checked". You`ll also find new and guaranteed units advertised, for legitimate use, in yachting magazines.
Night sights work on the principle of image intensification. A lens forms an image of the dark scene on a light sensitive cathode. This emits electrons which fall on a fluorescent screen and generate light. By amplifying the electron flow the final image is much brighter than the natural scene. You see the effect in nature films of animals at night.
Paranoics should be especially wary of any visitor who will never lose sight of their briefcase. It cost at least a thousand pounds more than the normal shop price. This is not surprising because it hides a microphone and miniature VCR, with a video camera that peers through a pinhole in the lock. As an extra option, the video camera is hidden inside a dummy cellphone which sits innocently on the table and connects with the briefcase on the floor by microwave radio link.
The law should safeguard us from this kind of intrusion, but in practice it seldom does. There is no blanket control over bugging and spying. Instead there is a tangle of different laws, which often make it legal to sell bugging equipment, but illegal to use it. So the vendor is in the clear, and the customer carries the can if caught redhanded. The penalties are severe, ranging up to two years in jail and unlimited fines. But victims first have to know they are being bugged, and then help the police prove it.
The Wireless Telegraphy Act, 1949 is still in force and bans unlicensed radio reception, as well as transmission and causing interference. Licenses are not available for the frequencies used by radio bugs (the VHF band 88MHZ to 108MHZ used for FM broadcast radio, the continuation of the VHF band up to 138MHz which is reserved for aircraft, and the UHF band 390MHz-45OMHz allocated to public mobile radio e.g. communication between a business and its fleet of vehicles.
Neither sale nor possession of unlicensed bugs is an offence. Using a bug is obviously illegal, but there is
often no way of proving who planted the bug or who is listening to it. Not surprisingly, shops seldom demonstrate their bugs working. Using a scanner radio to eavesdrop on cellphone conversations is an offence. But the authorities can only act when they have proof of reception. The Radiocommuncations Agency of the DTI could have prosecuted newspapers which published transcripts of the "Dianagate" and "Camillagate" tapes, purportedly cellphone conversations made by Princess Diana and Prince Charles. But the RA can only act if the scanner victims complain and positively identify themselves as the voices heard. The RA never received any formal complaint from the Royals, so no prosecutions were brought.
Recent updates to the Wireless Telegraphy Act let a government minister ban the sale, importation, manufacture and even possession of a particular piece of radio equipment that it is illegal to use. These so-called "Section 7 Orders" have already stopped the sale of CB radios and cordless phones that work on frequencies which are authorised in the US, but not in the UK. But the Section 7 weapon has not yet been used against bugging equipment. The Radiocommuncations Agency of the DTI is instead looking for proof of "incitement".
Installing offending equipment could very easily be encitement to break the law. Sale with advice, and a nod and wink, is risky too. ("How to bug a room" articles could also be.) The RA has already prosecuted a firm selling Videosenders. It was fined £4,800, plus over £3,000 costs. Another, selling car burglar alarms that work on unauthorised radio frequencies, was fined £2,000 with £4,000 costs.
As a result, electronics shops have recently become much more cautious about selling bugging equipment, and some have removed their window displays. The trend is towards mail order because it is then much easier to plead innocence of incitement. "All equipment is sold on the strict understanding that it will not be used in the UK and will be exported outside the EC" warns a catalogue sent recently to a UK address.
Some transmission and reception equipment is labelled "Type Approved", which means it can legitmately be used without a licence. A snooper could for instance legally use a two-way radio working in the UK`s approved Citizens` Band. But if hiding the transceiver involved breaking and entering, that would be a criminal offence in its own right. The Interception of Communications Act 1985 makes it an offence to read someone`s letters or listen to their telephone calls, including cellphone calls. Anyone who thinks their communications are being intercepted by an unofficial snooper, should go to the police. The same Act allows the Home Secretary to ask BT to tap phones if crimes are suspected.
Aggrieved parties, who think their phones are being officially tapped without justification, can apply for a review by an independent Tribunal. If Princess Di really believes she is under electronic surveillance from "enemies" in the Palace, she has an easy remedy.
British Telecom can act on interception too, by accusing the culprit of stealing electricity. The Data Protection Act 1984 makes it an offence to obtain personal data unlawfully, and store it on a computer. Storing speech as digital code could make bugging an offence under the data law.
The Department of National Heritage has for the last two years been working on new privacy laws which will make bugging, telephoto photography and electronic surveillance a criminal offence. Progress is slow because any welcome attempt at protecting people against tape recording and photography, would also have the unwelcome side effect of making it a criminal offence for a TV crew to shoot street scenes, for amateur photographers to take candid snapshots and for radio reporters to use a portable tape recorder to capture background noise in, for example, shops, offices and car parks, or for town centres to install security cameras in exhibition halls.
When Cellnet and Vodafone launched their analogue cellphone services ten years ago, the only technology available was analogue. The phones transmit speech, like ordinary broadcast radio, but at higher frequency (around 900MHz). Like a broadcast, the speech is "clear", not scrambled. The cellphone system uses two frequencies for each call, one for outgoing speech and one for incoming speech. The cellphone operators originally tried to reassure - or fool - their customers, by saying that this meant anyone who tried to eavesdrop on a call by tuning a radio receiver in to the cellphone band would only hear one half of the conversation. In fact this is not so.
The call always travels part of its way through the wires of the public telephone system, and this mixes the two halves of the conversation together. (This is why anyone using a telephone hears their own speech in their own ear.) Anyone who tunes in to either one of the two cellphone frequencies hears both parties.
When a cellphone call is dialled, the phone grabs the first available free frequencies in the area. So there is no way of knowing what frequency a call will use, and thus no way of targetting an individual caller. But a "scanner" does the next best thing. It sweeps rapidly through a chosen radio band and stops at any frequency on which there is a strong signal. The user can then lock the receiver onto that frequency, or let it go on sweeping.The first scanners were designed for amateurs who wanted to sweep the short wave ham bands for interesting conversation. When
cellphone services began the manufacturers quickly launched new models which also covered the 900MHz band. They cost under £200 and are widely available. Sale must remain legal, so long as the scanner can tune to at least one band on which listening is legitimate. But be warned. Anyone caught with a scanner which has been programmed to sweep an unauthorised band is at legal risk.
The new digital cellphone services (Hutchison`s Orange, Mercury`s One20ne and the pan-European GSM services offered by Cellnet and Vodafone) transmit speech as digital code. In itself this is no protection against eavesdropping. The coding
system adheres to a published standard which any manufacturer can use to build a decoder. But in Europe the digital systems use a powerful encryption system which scrambles the digital code so that it can only be deciphered by the intended receiver. So anyone worried about eavesdropping would be best advised to use a digital service. Because the encryption is so powerful, cellphone manufacturers cannot export to countries (e.g. in the Middle East) which are classified as hostile. The military does not want to help the enemy relay secret messages. Likewise as digital cellphone services open up across the US this year, it is likely that the speech channels will either be clear, or encrypted with only a weak encryption system. The law enforcement agencies want to eavesdrop on criminals and drug traffickers.
World wide bugging
The Iridium digital satellite cellphone system developed by Motorola will give world cover later in the decade, without any scrambling. Anyone with a digital scanner, anywhere in the world, should then be able to eavesdrop on any satellite cellphone anywhere in their area. It is hard to see how legislators can ever outlaw this, with any hope of enforcement. Loss of privacy is one more price we must pay for technological progress.
As with all controversial topics there are two sides to the coin. While the activity of covert surveillance may be fraught with legal potholes and moral minefields for those involved in it, the general public lie safe in their beds at night blissfully ignorant of just what is going on behind the scenes to provide this cocoon of social and economic safety.This framework of safety is under constant threat and attack. Overt terrorism is reported every day in the newspapers and is a global problem facing all nations. Extremist organisations have no limits to the lengths they will go to cause major social and economic disruption, and now, with the potential for obtaining nuclear material on the "black market" , the consequences of this threat are almost unthinkable. At the other end of the scale we have the Police forces facing increasingly clever and organised criminals involved in drugs, fraud, extortion etc. They may not initially appear as dangerous as the terrorist threat, but in actual fact they could potentially pose a far greater threat, as they slowly but surely eat away at the delicate fabric of our society.
This black picture would most certainly be an awful lot blacker if it were not for the constant use of information gained by the various security organisations through the use of covert surveillance, both audio and video. By making the mesh of the net tighter to catch the big fish we unfortunately snag a few of the smaller innocents. No system is perfect and that is the price we must pay for the blanket of security under which we all sleep. Those who stand in judgment of the use of this type of equipment should consider what is going on in the outside world, and just what life would be like without it.
On a far more mundane level, yet just as important to the victims involved, our everyday lives are often faced with attack from within, not necessarily physically. Very often these are situations that the Police cannot deal with for various reasons.
Take the case of the family who had ploughed everything into building their business up over the last twenty years. They had noticed that profits seemed to be dwindling slowly but steadily. A paperwork investigation by the accountant showed nothing obviously wrong or sinister. As things got steadily worse they decided to take action involving the use of covert audio and video surveillance and radio "tagging" of a certain number of their produced items.
What transpired was a shock to the family and almost disbelief by the Police. The appointment of a family "friend" into a position of authority two years previously had been a big mistake when he started to take away scrap by-product, rework it and sell it on at car boot sales.
The success of his venture led him to expand into taking large quantities of material to keep up with the demand. Not having the production facilities to work the material he had cleverly created a second company within the first with paperwork, orders, production and despatch all being run to his benefit.
The result of the information gained was a criminal prosecution and recovery of the company`s profits. This situation could not have been dealt with by the Police, they can only act when there is evidence of a crime and then only when, with their overstretched budgets and undermanning, there are no other more pressing cases to deal with.
Then there is the case of the family who, certain that their older son was the victim of drug abuse and having watched him slide from a sparkling academic career in medicine into personal hell, made the unenviable decision to monitor his telephone calls. Only to find that their son was the subject of ongoing blackmail by a group of drug pushers who had found out about the theft, by him in desperation, of a small amount of drugs from the hospital in which he was employed and were forcing him to steal more and more for their benefit.
Unfortunately these examples are far from exhaustive and over the twenty plus years I have been in this field I have seen a portfolio of tragedy which no level-headed, right minded person would disagree required, and wholly justified, the use of surveillance equipment. Where I believe the infringement of civil liberty was utterly insignificant in comparison to the benefit to society. Tim Jinks, Suma Designs
Other electronic terms somewhat related to surveillance
cctv lenses computer security dst fraud mi6 spymaster