“Normally the best way to bug is through a pinhole that is too small to see in the imperfections of the woodwork or the plaster. Visually, you wouldn’t find the pinhole.” (Researchers are at work to develop pinhole finders.) But even with a pinhole the presence of a microphone buried in the wall may produce a slight signal on the metal detector if it is just inside the plaster behind the pinhole opening. Now, Mr. Ward indicated, the tube mike has been developed. This permits you to put the mike several inches back from the pinhole. The tube, which can be a plastic resonator, leads from the pinhole to the mike and reduces the chances that the microphone will be detected by any metal-detecting device. Dr. Leo L. Beranek of the Massachusetts Institute of Technology, an authority on acoustics, has described devices that can be placed on the outside wall of a room under surveillance. Voices inside the room set up mechanical vibrations that may be detected by such a device placed against the outer wall. Most experts hired for counterintrusion work feel insecure unless they can inspect all rooms around, above, and below the room they are guarding for any signs of bugging activities.
As for the highly directional microphones that reputedly can pick up conversations from great distances, a sizable folklore on the reach of such microphones has developed. Published reports that they can pull in voices from 1200 feet away or through closed windows are apparently without basis. But apparently some do bring in conversations 100-150 feet away under moderately noisy conditions and up to 500 feet if conditions are ideal (quiet).
The first of these miracle mikes to receive much attention was the parabolic microphone, placed at the focal point of a reflector. Such giant saucers were first developed on a large scale during World War II, before radar, and proved to be much more sensitive than the human ear in detecting approaching aircraft. An effective parabolic mike requires a reflector with a diameter of at least three and preferably six feet. This makes it somewhat cumbersome for most sleuthing purposes, but it can be concealed behind bushes, or in an open truck, or in the darkened balcony of a conference room.
Another kind of long-range mike is the so-called machine-gun type, consisting of a bundle of tubes of varying lengths, each of which brings the sound to a microphone at the rear. Such an arrangement of tubes tends to eliminate most sounds not almost directly to the front. Cumbersomeness is again a problem. The picture of the one I saw in operation indicated that the longest of the pipes was about seven feet. The man using it was behind bushes. A Senate subcommittee was told that this type of mike proved to be practical in gaining evidence of blackmail involving a motion picture actor in California. The blackmailer, being suspicious that the man might wear a bug, specified that the actor meet him at a remote place on a beach and wear only bathing trunks. The actor complied but a machine-gun mike a few hundred feet away in the dark was able to pick up enough of their talk to provide incriminating evidence.
Still a third type of long-range mike is produced by Electro-Voice, which specializes in developing microphones for broadcasters. Recently it developed a single-barrel mike about seven feet long. All major TV networks have used it to pick up the voices of questioners at presidential press conferences . . . to pick up the sounds of distant bands in parades . . . and to pick up—from the side lines—the voices and sounds of body impact of players at football games. The National Football League now has banned it because it was picking up and broadcasting too many obscenities. Electro-Voice has had inquiries from—and made sales to—a number of customers who may well have been investigators, but it has no knowledge of how many are actually being used in investigative work, since these users keep pretty quiet about their methods of operation. Its big mike costs about $1000. A simpler non-electronic way to eavesdrop on distant conversations—if the eavesdropper does not need recorded evidence—is to employ a lip reader with binoculars.
One of the most prevalent forms of bugging is a concealed mike-transmitter on the body. Miniaturization has made this feasible; and unfortunately there is little reason to fear prosecution.
Many experts favor placing the mike behind the tie, fairly low down so as not to pick up interference from the heartbeat. Tape recorders are now small enough so that there is little chance they will be detected if taped to the body.
However the experts prefer concealed transmitters rather than recorders. The transmitter will broadcast to a tape recorder that can be several hundred feet away, and even a fairly powerful transmitter can be made much smaller than a good concealable recorder. Also it can operate without reloading longer than a tape recorder. And even if a person is caught with it during a frisk the information obtained up to that point cannot be destroyed, and if necessary help can be dispatched. The transmitter can be carried on a coat pocket with its antenna going up to the armpit and down the sleeve. One of the best places to put either a transmitter or small recorder, according to a man who has submitted to police frisks to test his theory, is just above the coccyx. Another favored way of concealing a transmitter and mike is to pack them inside a king-size cigarette package designed to feel, to the touch, soft as a package of cigarettes.
To complete our rundown on bugging devices, there are a variety of tailing aids that can be attached to an automobile. One simple transmitter broadcasting a pulsing tone signal is mounted on four magnets and can be attached to any clean metal surface under the car in a matter of seconds. It can be heard for a mile.
The “art” of wiretapping—which is at least technically a more illicit form of eavesdropping—has also seen some advancements in recent years. One is a miniature transmitter that can be attached to the tapped listening post. This is not only more convenient, but has the advantage of reducing the chance the tapper can be traced if a tap is discovered.
Tappers frequently pose as telephone repairmen, and some who engage in tapping on a large scale even buy or build imitations of the green telephone-company trucks.
Tools for the more elementary kinds of direct wiretapping cost less than $25. And for $4.25 one can purchase a little device that feeds a telephone conversation into a tape recorder. It can be installed in three seconds by pressing its suction attachments against the back of the telephone receiver.
However, when one gets into transmitters, automatic recorders, and many of the microphoning tools that we’ve discussed, the prices soar. A professional eavesdropper is likely to require an expensive bag—or truckload—of tools. An examination of four catalogues issued by producers of surveillance equipment (Mosler, Tracer Electronics, Inc., W. S. J. Electronics, and R. B. Clifton Electronics Surveillance Equipment) gives some idea of an eavesdropper’s overhead. Here are some sample prices:
—Transmitters for wireless wiretapping. Prices range from $65 to $200 depending upon whether signal must be broadcast one block or three.
—Picture frame transmitter, $215.
—General-purpose transmitter to be planted inside room, $95 to $137, presumably depending on quality.
—Transmitters for concealment on body, $150 to $220.
—Device for automatically starting tape recorder when conversation begins on tapped telephone line, and stopping when conversation stops, $76 to $105.
Since a few states ban even the possession of wiretapping equipment by private parties, the Clifton catalogue states at the end of its price list: “Caution—in many parts of the world there are certain laws which prohibit using some of the items above. It is the sole responsibility of the buyer (and not the seller) to ascertain through legal counsel how these laws may apply to the use of each item purchased.” Tracer Electronics simply notes after some of its items: “Sold for use subject to pertinent regulations.” And the proposed FCC regulations restricting use of radio transmitters for electronic eavesdropping, if and when promulgated, will in no way affect the selling of such devices, but will only make the users warier of their legal position.
A quite different kind of electronic surveillance—and control—has become possible through the development of the giant memory machines. Each month more and more information about individual citizens is being stored away in some gigantic memory machine. Thus far, the information about individuals is usually fed into the super-computers to serve a socially useful or economically or politically attractive purpose. But will it always be? This might especially be asked concerning those memory machines that are building up