Spies GSM Technology
Conventional radio transmitters as we have discussed are now becoming obsolete due to GSM (mobile phone) technology. If we think about it, the old style device requires the eavesdropper or recording receiver to be located relatively nearby which is not always tactical or practical. In addition, the transmitted radio signal can easily be detected and listened in to by almost anyone with a radio receiver or scanner.
With GSM, technology all has changed. If you imagine the working parts of a mobile telephone re-engineered and housed in a protective casing; add to it a long-lasting power supply and a high gain microphone and you have your ultimate secure listening device with unlimited range. Think about it, the device is on ‘standby’ when in situ and uses up very little power. You dial into the device from a telephone or computer from anywhere in the world and are then able to listen in to the conversation within the immediate area. What is more - the signals being transmitted cannot easily be intercepted as they are digitally encrypted, this is the future of audio monitoring as we know it and by the way, it is also good way of bugging cars as Gerry Adams and Sinn Fein discovered in the recent past. MI5 fitted a most intricate listening device into a vehicle used by Mr Adams.

One of the most effective audio transmitters I have seen is actually a transmitting microphone used by performers on stage and by film crews. The small system is comprised of a small transmitter normally worn on the belt connected to a high gain microphone. This transmits to a dedicated receiver and the audio clarity far outshines any surveillance device on the market today and at a fraction of the cost.

http://www.eyespymag.com/tool2b.htm

http://www.eyespymag.com/tool4b.htm

http://www.eyespymag.com/tool5b.htm

http://www.eyespymag.com/tool6b.htm
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