Bug detectors are designed to detect different types of listening devices, including wireless microphones, transmitters, and audio recording devices. However, there is no single detector that can detect all types of listening devices, as they come in various shapes, sizes, and transmission methods. Some bug detectors are more sensitive and advanced than others, making them capable of detecting a wider range of devices.
Most bug detectors work by scanning for radio frequencies emitted by these devices. However, some listening devices may use different transmission methods that are not easily detectable by these detectors, or they may save data on a local memory card, thus emitting no signal.
It is also important to understand that bug detectors are not foolproof and may not be able to detect hidden listening devices that are well-hidden or have advanced features to avoid detection. Therefore, it is important to use bug detectors as one of many tools to protect against unauthorized surveillance and to seek professional help if there is a suspicion of being under surveillance.