Distance Microphones - Non Local Surveillance

Introduction to Long Range Distance Microphones

   Surveillance devices can now be used by an eavesdropper from a distance, without invading an individual's premises. These remote listening devices are a high-tech means of surveillance used commonly in the marketplace. By definition, a remote listening device is an electronic unit, that amplifies sounds or conversations from a distance, without physical equipment located at the point of detection.

   Generally, long range surveillance systems such as acoustical boom microphones, microwave and laser reflection systems and shotgun microphones are used in a situation in which the surveillancer has a "line of sight" view of the occupants under surveillance. The surveillancer can then use the physical surroundings of the area as a camouflage to avoid detection. 

A few examples of what long range distance microphones look like: 

Main classifications of audio distance surveillance devices: 

  • Acoustical Amplification
  • Laser Reflective Amplification and Demodulation
  • Infrared Reflective Amplification and Demodulation
  • Microwave Reflective Amplification and Demodulation
A general listing of areas where this "undetectable" surveillance can occur: 
  • Windows are a top place for eavesdroppers to use "boom" microphones and laser reflective / microwave devices, as window glass will vibrate, much like that of a speaker cone on a stereo speaker, conducting sounds better than a solid wall..
  • Walls are the next area for listening in.. Sound can be amplified several hundreds to thousands of times, and sent to the eavesdropper through plaster and drywall areas.
Overview of all distance surveillance devices: 
  • Easy to use - almost anyone can operate
  • Inexpensive to Expensive in cost - depending on ranges of complication and quality 
  • Undetectable by conventional methods - difficult to detect with equipment 
  • Does not physically invade personal or business property
  • Often preferred method of surveillance
  • Can be used portably or stationary mounted for continuous use
  • Overall the most cost effective means for a surveillance job

Introduction to contact microphones:

A contact microphone is a device, in which an electronic or electret microphone is placed on a premise, to directly amplify, and transmit information by direct wire or other means to a surveillancer. 

An example of a contact microphone system: 

Contact microphones can be placed: 

  • Windows are a top place for eavesdroppers to use contact microphones, as window glass will vibrate, much like that of a speaker cone on a stereo speaker, conducting sounds better than a solid wall..
  • Walls are the next area for listening in.. Sound can be amplified several hundreds to thousands of times, and sent to the eavesdropper through wired means.
  • Ceilings are an extra issue. This type of intrusion again may be planted ahead of time by a suspecting individual when you are not home or in the office.
  • Air ducts & Water pipes have been known to carry sound hundreds of yards, through large buildings and apartment complexes. 
  • Overview of all contact microphones: 
    • Easy to use - almost anyone can operate
    • Inexpensive in cost 
    • Undetectable by conventional means
    • Physically invades or occupies space in a residence
    • Widely used by surveillancers in the same building


        If you suspect that you are under surveillance by long range distance surveillance devices, or by contact or buried microphones in you residence, there is a simple solution. Since sound waves can travel great distances, even through solid walls, windows and ceilings, masking the conversations at the source, would be an answer to the problem. 

       If the sound from your conversations is also masked at the point in which the acoustics are more likely to travel through, such as through windows or exterior facing walls, then the conversations in the premises can be electronically jammed. 

      This type of counter-surveillance electronic technology exists and is very plausible without becoming expensive. In fact, it is very easy to use and requires no maintenance, and is unnoticeable to the inside occupants of the premise. 

      Our Acoustical "Random" Noise Generator uses this technology as a counter-measure to undetectable surveillance devices and methods. 

      The ARNG-2000 creates a "random" unfilterable white noise which can be used as a perimeter protection against "long range" listening devices. Our unit is designed to be mounted inside your home or office, to an exterior facing window, wall, ceiling, or other suspected area of intrusion. It literally "scrambles" the audio (voices) that the surveillancer receives, making it impossible to interpret and/or filter out the sound. To the user, inside the home or business, no audible noise or "hissing" can be heard by the occupants using this device. Basically, the ARNG-2000 will jam the sound at the source. 

      Check out our products page for the Acoustic Random Noise Generator

    At an ending:

    As to solve any problem, taking a logical approach to solve a particular surveillance situation is always the right approach. Now with a new knowledge of how surveillance devices work, where they can be placed and how to identify common types of distance surveillance devices, the individual can now take affirmative action with the proper equipment. 

    Remember that not all equipment that is sold in the open marketplace for counter-surveillance is suitable, nor has all the features needed to provide detailed counter-measures. 

    Our test equipment uses the latest technological innovations to help the individual or technician in the aid of locating and positively identifying surveillance equipment. 

    Remember, that our equipment is only a tool used to aid a person in the field of counter-surveillance. Only a human being using knowledge, skill, and a methodical approach can find a surveillance device and remove it from operation using a proper counter-measure.

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