Surveillance Devices

There are many ways for your privacy to be invaded, below we have outlined some of the more common methods for you to consider.

Telephone Taps

This form of surveillance often requires access to the property or a telephone junction box to achieve. A device or modification is attached to the phone or line that allows the listener the ability to listen to phone conversations within the property or room audio from around the device. Methods of transmission of this audio can include carrier current, radio frequency or remote recording etc. PABX systems may even transmit audio in a digital format; however with access to the system you can still produce room and conversation audio.
Telephone Taps can also be engaged at the exchange by Telecommunications providers under warrant by Law Enforcement agencies. These taps will not be detected at the property.

Hardwired Cameras & Recorders

Using existing fixtures in a property allows the eavesdropper access to wiring and in some cases many different substitutes for a standard microphone such as speakers, sirens and intercom systems. Connecting a microphone to these wires and then connecting a hardwired recorder will eliminate the ability for spy shop detectors to notice RF energy. A hardwired camera could also take advantage of this wiring and potential power supply.

Common Radio Transmitters

There a lot of radio transmitters on sale via the internet, ranging from cheap spy shop FM bugs up to UHF remotely activated devices. The ranges of these devices can vary greatly, in some circumstances even 50 kilometers away. Cheaper devices often have an effective range of only 500m-1000m and typically sell for around $100-$300 and suffer from radio traffic interference. These devices are often considered throw away devices because of their cheap cost and short battery life.

Advanced Radio Transmitters

More advanced transmitters include features that make them undetectable to the spy shop hopefuls. A burst transmitter for example may spend 1 hour gathering audio from a particular area and only two seconds to send that information. The device will then appear dormant until it needs to send further audio, making it virtually impossible to locate with a spectrum analyzer or a handheld detector.
Frequency hopping is also used to transmit data over a number of pre-determined frequencies. This technology along with the use of a broad spectrum signals will also reduce the opportunities for detection by common detection equipment.

Directional Microphones

The use of directional microphones allow the eavesdropper the ability to sit in a position observing a window and pick up audio from that room if the window is open and minimal audio interference is present. More advanced laser devices are available at a premium cost, but suffer from interference issues.
For example if you were to aim the laser directly at a window to obtain room audio the laser would send back the vibration of a voice inside the room and reproduce it as audio. But if there is any noise outside, it can cause the glass to vibrate giving the eavesdropper inaccurate audio if at all.

ESD does not sell or supply listening devices.