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THE OMINOUS EAR
by Bernard B. Spindel
Chapter 17. - Technical Aspects
The telephone instrument dates back to the early 1880’s. Wiretapping devices in existence at that time were extremely crude and basic – a condenser-equipped telephone earpiece through which one was effectively able to monitor a communication, During Prohibition the wiretapper graduated to the use of headphones for monitoring. To the present day, these two devices remain as basic and crude wiretapping instruments.
With the advent of radio and in the early 1930’s, when the vacuum-tube amplifiers became commonplace and the loud-speaker replaced the old horn-type speaker, life became much easier for the wiretapper. In the early
1930’s, the magnetic recording head became less expensive, and recording discs were added to the wiretapper’s tool and accompanied the man with the headset as a replacement for the stenographer’s notebook.
During World War II, the development of magnetic wire recording, together with the miniaturization of electronic tubes, made possible smaller, lighter and far more efficient eavesdropping devices. The high-gain amplifiers and associated components – fast becoming cheaper and easier to obtain because of mass production methods – made even more equipment available at lower prices.
In the late 1940’s, magnetic tape recorders were introduced and the transistor replaced the bulky vacuum tubes and heavy and costly power supplies. The equipment shrank from shoe-box size to the size of a package of cigarettes.
In 1955, I testified before a Congressional Committee that each of the more than fifty million telephones in the United States could, with the attachment of one wire, be converted into live microphones that conducted sound even when the phone was not in use. Such a microphone could pick up a whisper within thirty-five feet of the telephone and send the signal over telephone wires to a listening post where, at the first sound, a recorder would turn itself on and then turn itself off when the voice was no longer to be heard. This is know as a “voice-actuated stop-and-start” mechanism. Late in the 1940’s I developed the first undetectable, fully automatic telephone stop-and-start mechanism that turned the recorder on and off when the subject’s phone was lifted out of the cradle. It then recorded both sides of the conversation and automatically stopped running when the telephone was hung up. It was at this time that I built the first recorder capable of operating for fifty hours without wasted tape because it was activated only while a conversation was actually taking place.
Law enforcement and professional eavesdroppers were quick to pick up old or new technical principles and adapt them for eavesdropping purposes. I testified and demonstrated before the Committee in 1955 that a parabolic microphone – and there were numerous types and models available at that time – could, without the use of any wires or a radio transmitter, pick up the conversation of people in a rowboat out in the middle of a lake, and record it on shore.
Highly sensitive phone cartridges were developed, and these were adapted and utilized as contact microphones to pick up conversations through walls and into other rooms. Along came especially designed microphones that did this job even better. Electronics progressed and special filters became available which could eliminate background noises and limit the input to eavesdrop equipment by concentrating only on sounds of the human voice. Such efficiency is now improving to a point that background noises from cards, trucks, etc., are almost entirely eliminated.
As eavesdropping has graduated from science to art, specialized devices have been produced specifically for this field. A prime example is the non-magnetic microphone developed by the Russians. More than forty of these were installed within the walls of our Embassy in Moscow when the building was being constructed. Our State Department maintains a special staff of technicians trained and equipped to detect such devices. However, these microphones contained no metal. They were of ceramic construction and had hollow wooden tubes through which sounds originating in a particular room were transmitted through walls.
The search equipment used to detect buried wires and microphones of normal type is similar to that used in mine detectors. A tracing of a wall with one of these devices indicates every wire, nail or strip of metal buried within, but it failed to indicate the Russians’ ceramic microphones, which remained intact inside the Embassy walls for eleven years. Only the information passed along by a defector who became an informant alerted us to the fact that Embassy conversations were being leaked. In total frustration, it was decided to tear the walls apart in a desperate attempt to find the microphones.
The walls of one room were ripped out and the existence of these mikes was finally revealed.
In my testimony in 1955, I had warned the Congress that experiments indicated that it was already possible to take the conversation out of a room without benefit of wires, without benefit of radio as we knew it then, and without the need to install any device – in fact, without ever entering the particular room to be bugged.
Directly following this testimony, the Russians displayed their electronic prowess by utilizing a rather old principle based on what is known as a cavity resonator. A replica of the American eagle was presented as a gift to U.S. Ambassador Harriman. The Ambassador proudly placed it in his own office. Buried in the eagle was a transducer – a piece of metal about the size of a half-dollar, with no connecting wires. By beaming a high-frequency signal from a distance, aimed directly at the room containing the transducer, conversations taking place within the room were reflected back to the listening post. Again our State Department security agents did not detect this apparatus until they were alerted to its presence by other sources.
When I made the disclosure of this type of technology to the Congressional Committee, scientists in government and in private industry did not know what I was talking about; still others maintained the usual “will not confirm or deny” attitude and, in effect, pooh-poohed my testimony. Actually, the device to which I referred involved a principle that has never been scientifically documented, and I have never divulged the technology behind it through fear that even in official hands it might be misused against private citizens.
Sub-miniaturized devices capable of sending a signal on infra-red light beams which are invisible to the human eye, and traveling long distances without the need of radio or wires, have made novel transmissions of eavesdrops a reality. In order to detect these beams, one must either find the unit itself or be in a position to find the exact angle at which they are being emitted. They travel in the same way as do beams from a powerful searchlight. Furthermore, the use of such a device does not come under any rules or regulations or laws of the Federal Communications Commission.
A more sophisticated device is the cesium transmitter and receiver. In its pure form, cesium is a rare metal and expensive. There are standard cesium lamps which transmit light similar in characteristics to micro-radio waves. This light is limited to the line of sight as covered by the permissible distance one would encounter in the curvature of the earth to the horizon. Some interesting experiments with miniaturized cesium transmitters have permitted these light waves to go beyond the horizon by aiming them upward into the sky where, regardless of the atmosphere, they act as a mirror to a searchlight, thus transmitting the signal for many more miles than had previously been believed possible.
We have all been accustomed to remote-control garage door openers, activated by pushing a button in the car as we approach the garage, causing the doors to open and the driveway lights to go on.
We are equally accustomed to the sonic remote-control device developed by Zenith which enables one to turn a television set on and off, and to even change the channels or adjust volume and picture, without the use of connecting wires. This employs the principle of sonic transmitting signals in the inaudible range between the limits of the human ear and low-frequency radio signals. People were shocked when Life Magazine showed a martini containing an olive which housed a built-in radio transmitter, utilizing the toothpick as an antenna. While this novel device is excellent for illustrating the miniaturization possible in radio transmissions, it is of limited practicality. However, a slightly larger transmitter, the size of a pack of matches, can easily send a signal the distance of several blocks. Concealed under a chair or bed, it can indeed transmit some very interesting signals. The sonic transmitter is equally capable of picking up a whisper in a room and – without any detectable wires or radio signals – transmitting it to a sonic receiver which restores the signal to the audible sound originally picked by by the microphone. This device also eludes the jurisdiction of the FCC and does not violate Federal law.
The Federal government has not yet deemed it advisable, after more than a dozen Congressional hearings, to make it unlawful for one person to eavesdrop on another person.
One can readily understand the problems involved in locating these sophisticated devices while doing a “search.” The problems become even more complex in view of the fact that – at the will of the eavesdropper – all eavesdropping devices can now be turned on and off by remote control.
To illustrate this more fully, let us take the installation of a “bug” in the office of a subject. The eavesdropper might rent quarters nearby which would enable him to observe the comings and goings of the subject by the push of a button that could send a sonic, sub-sonic, cesium, infra-red or radio signal. This signal could be further sensitized by the possession of special tones or keying code signals; should someone attempt to do a search for the device, the eavesdropper would immediately hear the technician at work. By again pushing the control button, the eavesdropper could de-activate the unit or turn it off, leaving the searcher without a signal to follow.
In a case involving the conversion of a normal telephone into a live microphone, the eavesdropper supplies – from his remote listening post – the battery voltage necessary to make the microphone become alive. Again, should he hear someone attempting to make an inspection, he removes the battery voltage, and only a carefully trained searcher would know how to identify the telltale indications of the “hot” telephone mike.
In the more sophisticated micro-miniature microphones and amplifiers, battery voltage to activate the devices is also supplied from the listening end. Again, since the voltage can be removed should the eavesdropper sense the danger of discovery, the only indication remaining would be the device itself, and it would generally be concealed in such a way that a mere pinhole would be visible. If this kind of device were to be placed behind wood paneling that contained many nail holes, the mike-intake hole would appear no different than any of the other tiny perforations.
I demonstrated publicly the sensitivity of a microphone concealed within an ordinary duplex electrical wall outlet – the kind of outlet that might be found in any home or office in the United States. This ordinary-looking wall outlet, I explained, had only a sensitive microphone. There are other models in existence which, in addition to the microphone, have a built-in amplifier that can send a remotely controlled signal ten or more miles. Another model has a built-in miniature radio transmitter that takes its power from the power line and radiates its signal through the air. Still another model takes its power from the power line but does not radiate its signal through the air; instead, it sends back over the power lines a radio frequency that can be picked up anywhere in the same building or within the main power-line circuits feeding that building. By fancier manipulation yet, this signal can be made to go even greater distances by bypassing the power transformer on the block.
It was in 1955 that I made public a device which, once installed, would permit me to call a specific telephone number from anywhere in the United States, listen in on a telephone conversation if one were taking place and then, when the party hung up, continue to listen to conversations being held on the premises, all by long-distance remote control.
There are other sophisticated devices, unknown to the public and to law enforcement, which remain closely guarded secrets of the private investigator’s trade. Frightening as these devices are in their potential, we must face the fact that we are now entering an area of even greater technological development, one that staggers the imagination.
The technical know-how incorporated into these devices, is, in general, used for legitimate purposes in other fields. In recent years we have heard much about the laser beam. There are over two hundred companies engaged in laser research and development. The laser offers promising possibilities in the medical field since its ability to cut is so fine that a scalpel no larger than a pinpoint could not duplicate its delicate accuracy. There are harmful effects possible with the laser, too. Experiments have shown that the laser could be beamed through a closed window to take out the sound in the room. The only limiting factor to this feat at the present time is the size of the equipment required. As soon as miniaturization is achieved, such eavesdropping will be a simple matter. It is safe to predict that in the near future the laser beam will not only be used to take the sound out of a room, but will also be used to take out a visual image of whatever is going on within that room.
As I pointed out to the Legislative Committee in Boston, Massachusetts, there is not one state in the Union that has included in its eavesdropping laws the word “picture”. The statutes refer only to the overhearing of a spoken word. I recommended to the Committee that it include the idea of “picture”. As I explained, the new development known as video telephone, introduced by the telephone company at the New York World’s Fair in 1965, enables two parties to not only converse, but to also see each other on a TV screen at the same time. The telephone company proudly stated that this service would soon be expanded and made available to any subscriber who wanted it. I cautioned the Committee that, just as the ordinary telephone in the home can now be adapted into a live microphone, circuitry would enable the technician to jump the video phone in a way to make the video portion send out a continuous picture even when the phone was not in use. Frightening as this may seem, it does not compare with the possibilities that lie ahead.
from Chapter 18 - A Matter of Privacy - A final thought...
In this complicated modern world which has given us inter-continental ballistic missiles, satellite spies and atomic warheads, and which has reduced warfare to split-second, push-button decision-making, we have been forced to grant to our national leaders sweeping emergency powers that would have made our Founding Fathers shudder. We can accept all of this because it affects not only the survival of our country, but the future of the world.
In every other area, however, we must strengthen our individual freedom and our personal liberties. We have the money, the technical know-how and the man-power to keep ourselves free from external aggression. But advances in the technology of eavesdropping have made possible the total invasion of our privacy. We are in serious danger of destroying from within the very freedom we so earnestly seek to preserve. It will serve us well to remember that “where justice ends, tyranny begins.” *
Copyright © 1968 B.R. Fox
Library of Congress Catalog Card Number: 68-18702
* On the United States Department of Justice building in Washington DC, there are five words engraved in stone... "Wherever Law ends, Tyranny begins." John Locke, 1690
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