Radio frequency defense film, also known as RF
attenuation window film or anti-eavesdropping film, protects homes or
workplaces against radio frequencies and electromagnetic radiation. The
RF film that the customer requires meets strict security requirements
for facilities handling classified or other sensitive information. The
government customer has requested to remain anonymous for security
reasons. more
We've been down this road before, in 2007 and 2009.
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Listening & Anti-Eavesdropping Device
(18 years ago this month)
Abstract
A method and apparatus for transmitting information from a conversation in a room to a remote listener comprising selecting a structure (101) in the room which is capable of supporting vibration, selecting an electromechanical force transducer (90) which has an intended operative frequency range and comprises a resonant element (84, 86) having a frequency distribution of modes in the operative frequency range, mounting the transducer (90) to the structure (101) using coupling means (68) whereby the transducer excites vibration in the structure, positioning a sensor to detect vibration in the structure (101), determining information from the detected vibration and transmitting said information to a remote listener. There is also provided an anti-eavesdropping system which is the reverse of the method and apparatus according to the first and second aspects of the invention. (self-licking ice cream cone) more