Abstract: A hand held detection device for detecting electromagnetic waves at at least one predetermined frequency has an elongated conductor member having a bottom end portion for grasping by a hand of a user and a top end portion, the elongated conductor is configured to function as an antenna at the predetermined frequency. An inductor is supported on and electrically connected to the top end portion of the elongated conductor. A wave detection circuit is supported at the top end portion of the elongated conductor member one the inductor. The wave detection circuit includes a rectifier diode for rectifying high-frequency alternating current received in the inductor via the elongated conductor to produce a direct current. The wave detection circuit also includes an indicating means for indicating a presence of a direct current produced by the rectifier diode, the indicating means and the rectifier diode are serially connected to form a series circuit, and the series circuit is connected across a portion the inductor.

Abstract: A hand held detection device for detecting electromagnetic waves at at least one predetermined frequency has an elongated conductor member having a bottom end portion for grasping by a hand of a user and a top end portion, the elongated conductor is configured to function as an antenna at the predetermined frequency. An LC-resonance circuit is supported on and electrically connected to the top end portion of the elongated conductor and the LC-resonance circuit is tuned for accepting the at least one predetermined frequency. A wave detection circuit is supported at the top end portion of the elongated conductor member. The wave detection circuit includes a rectifier diode for rectifying high-frequency alternating current received in the LC-resonance circuit via the elongated conductor to produce a direct current.