Here is a RF wireless signal detecting wand that finds GSM/3G bugs, wireless video cameras, and WiFi transmitters. It has normal, vibrating, and audio modes with a frequency range of 50-6000 MHz. It can be used to detect analog and digital transmissions as well as Bluetooth and WiFi 2.4/5GHz.
The device is ideal for beginners and pros performing sweeping tasks. The battery lasts up to 20 hours.