Electronic Eavesdropping Devices. History And Widely Spread Types
It's 21st century now, we live in an informational era, when information is the most valuable resource. And with the development of wireless technologies it becomes really hard to keep our information in secret and protect it from third parties. These days special devices, such as GSM bugs, hidden microphones and lasers are available to almost everyone and are used for spying. Many people don't even know that eavesdropping bugs appeared a long time ago. The first widely known episode of their utilization was in 1972 in USA. A group of specialists from Nickson's election headquarters quietly slipped into headquarters of democrat's party candidate and installed hidden radio microphones, so they were able to hear what their counterparts are talking about. And that was probably the first time when eavesdropping technology was used not only by law enforcements or secret services, but by common people. And probably form that time various eavesdropping bugs are used for political and industrial espionage.
Nowadays, there is nothing really complicated about those bugs. Any educated and experienced specialist may organize a whole eavesdropping system. That's why today we at Jammer-Store decided to tell our readers about the most widely spread types of eavesdropping devices, the way they work and how to detect, or disable them.
The main disadvantage of the wireless microphones, which are powered with a battery is the limited working time, but they are far more easy to install. Those small bugs have different working range, in which they are able to hear voices and it varies between 15 and 80 feet. And transmission radius may be really huge, between a dozen and hundreds of meters. Sometimes evildoers may use a network of relays, to broadcast that signal even further.
Such a wireless microphone is the most convenient device for hidden eavesdropping. They consist of the microphone, power source and a radio transmitter. Those small devices may be powered with a battery, but in that case they will work for a small period of time. Advanced versions are powered from the mains. Those devices are frequently installed in wall sockets, lamps and other places, where they are really hard to find.
Wireless microphones may use different frequency ranges, the most widely spread are 140-200 and 450-480 MHz. The higher the frequency – the bigger is the transmission range and the power consumption. Also, higher frequencies penetrate walls and other obstacles easier. Fortunately, it is possible to detect those kind of devices with a special receivers. But advanced version may have a special signal modulation, and you won;t be able to intercept and to, actually, hear them. Ina that case you can try block their broadcasting with UHF/VHF jamming device.
Network transmitters are small devices, that are installed into various electrical appliances, they gather and transmit information in low frequency audio range. They use an electric power grid to send the signal, and it may be received from any wall socket of the same segment of the grid.
The main disadvantage of that kind of eavesdropping bugs is that that the first transformer will corrupt the signal, so you will have to stay really close to the targeted area. Also, it will take some time to install a bug like that, because it has to be connected directly into the power grid. We should also mention that there is no universal way to block them. You should simply check all electrical appliances and make sure that nobody makes anything suspicious with them.
GSM bugs are acting principally the same as the most primitive mobile phone. The bug is powered with a battery, as a rule it is the most widely spread Li-Ion battery. It consists of the microphone and a GSM module with a SIM card of the local mobile carrier. Once the bug detects a noise around it, it simply calls a certain phone number and evildoer listens to everything that is going on near the device. The benefits of the device are: wide working range, it may work anywhere, where there is a GSM coverage and very simple installation process. Also, they are widely spread and any one can buy such a device on the Internet. Those bugs are popular and are the main reason why big companies have GSM signal blockers in their conference halls and offices of high executives. That's probably the only reason to block transmissions of those devices.
The main trick here is that your voice makes a table to vibrate, sensor reads those vibrations and transmits them to a receiver, which transforms them into sound. Those microphones are highly effective, but it takes lots of time to install them. Also you will have to stay really close to the target.
Stationary microphones can be installed and disguised in a wide variety of places. They are connected with a central receiver with help of small wires, which are disguised too. In general, you can attach a piezo sensor to an office table and it will work as a microphone.
Also, we should mention, that with the development of modern smartphones the danger of eavesdropping grows, because evildoers are able to use your own smartphone as a bug. It is rather easy to install a special app, which will simply make your smartphone to dial a certain phone number and to work as a GSM bug. So, as you can see, there are lots of special devices, which are used for stealing information. As we've already mentioned, they are usually used for political and industrial espionage, but as long as information is the most valuable resource and those devices are widely spread – it is better to be prepared to face eavesdropping.