Here is a camera finder with RF detector that helps you find hidden cameras installed in any room. It has red LEDs and a viewfinder to locate the lens of any camera. There is also a detector to pick up RF transmission. It can locate signals up to 30 feet and locate a lens from 3 inches.
The device has a detection frequency range of 1MHz－6.5GHz. The rechargeable battery lasts up to 5 hours.