One of the most popular audio surveillance equipment is listening bugs. Phone taps or room bugs as they often referred to allow you to eavesdrop easily and professionally. Listening bugs can be very tiny in size, thus making your audio spying 100% covert.
A spy listening bug is generally speaking an electronic device made of microphone and a radio transmitter. Sound waves coming from the source are caught by microphone, which turns them into electric signals. This signal is then transferred into a radio transmitter inside a listening bug device. Such audio signals can be listened to or recorder with audio recorders.
Did you know that listening bugs can be active, passive or wired? If you don’t know what these terms mean, here’s a brief description of each:
- Active listening bug – Audio transmitter in these bugs is always active. It means it’ll transmit sound waves it catches non-stop and there’s no way to turn it off. It’s the most basic form of listening bug device.
- Passive electric bug – These bugs can be deactivated from a distance. By using a sound or some other signal. They’re hard to detect and obviously more efficient. You don’t drain battery power by constantly listening, you can turn it on or off any time you want.
- Wired listening bugs – As the name suggests, these bugs don’t use batteries. They use AC power (or sometimes DC power from a vehicle) to ‘feed’. You can leave these devices for long period of times and disassemble when audio surveillance is done.
While a common perception of a listening bug is that it’s tiny, sometimes even digital voice recorders can be called bugs. As long as the listening device contains microphone and transmitter people call them spy bugs.
One thing to note is that transmitting range is not unlimited. The further the receiver with transmitter are from the microphone, the weaker the sound waves will be. This means listening bugs can’t be used for long distance surveillance without directional antenna of some sort that amplifies the sound waves.