Patent ID: 7148802

Claim:
A direction finder and locater utilizing a synchronous detector comprising a remote unit and a target unit wherein: (a) the remote unit comprises: (1) a housing; (2) a power source; (3) a remote unit radio signal transmitter; (4) a directional antenna and a second antenna located approximately three feet from the directional antenna; (5) an operator controllable activation device that when activated causes the remote unit radio signal transmitter to transmit a first radio signal with a wavelength of approximately 13 inches; (6) a remote unit radio signal receiver tuned to receive a second radio signal transmitted from the target unit, the second radio signal having an amplitude; (7) an electronic amplitude measurement circuit to measure the amplitude of the second radio signal; and, (8) a visible display comprising a plurality of indicator lights that shows the operator an indication of the amplitude of the second radio signal wherein: i. the said indication changes as the remote unit points toward or away from the target unit; and, ii. the said indication changes as the remote unit moves closer or further away from the target unit; and (b) the target unit comprises: (1) a housing; (2) a connection to a power source; (3) two antennas; (4) a target unit radio signal receiver tuned to receive the first radio signal from the remote unit; and (5) a target unit radio signal transmitter that continuously transmits the second radio signal in response to the first radio signal.