Abstract: The present invention comprises a hand held, battery operated water current velocity measuring device designed for use with contact closure water current meters. The apparatus differentiates and amplifies incoming DC signals generated by the current meter into both AC and DC signals, which are then sent to a microprocessor. The microprocessor, using operations research processing, samples and evaluates both signals to determine if a contact closure has occurred (e.g., when the current meter has completed a revolution) and to distinguish an actual contact from external voltage or spurious noise pulses. Once the microprocessor has verified the occurrence of a contact closure, the microprocessor alerts the operator to the contact closure. The information may be transmitted via FM band radio frequency to one or more appropriately tuned FM radios.

Abstract: A method and system are provided for determining the level of a body of water, whether free flowing or stationary. Positionable mirrors are located at an area adjacent to but spaced from the body of water. The mirrors direct a laser beam at an angle to true vertical onto the surface of the body of water such that a portion of the beam is reflected from the surface. A receiver is located at a known distance from the mirrors on the opposite side of the body of water and in a common horizontal plane. The receiver receives a reflected laser beam and redirects the beam to a signal detector. A controller for the mirrors determines the angle to true vertical at which the mirrors are set after receiving an output from the signal detector. A simple calculation, based on the determined angle and the known distance between the mirrors and the receiver is then made of the distance from the common horizontal plane to the water surface so as to determine the water level.

Abstract: A method and system are provided for determining the level of a body of water, whether free flowing or stationary. A rotatable reflective element is located at an area adjacent to the body of water. The reflective element is driven by a rotating motor shaft and includes a reflective surface extending 45° to the shaft axis. Rotation of the reflective surface provides scanning of a laser beam directed axially thereon. During scanning, the beam is directed at an angle to true vertical onto the surface of the body of water such that a portion of the beam is reflected from the surface. A detector array, located on the opposite side of the body of water and in a common horizontal plane with the reflective element, produces an output after receiving the reflected beam. A controller arrangement, including a counter which begins counting when-the scanned beam is vertical and which stops counting when a signal corresponding to the array output is received, determines the scan angle to true vertical.

Abstract: The present invention comprises a hand held, battery operated water current velocity measuring device which provides more reliable measurements than conventional devices. Designed for use with contact closure water current meters, the proposed apparatus differentiates and amplifies incoming DC signals generated by the current meter into both AC and DC signals, which are then sent to a microprocessor. Utilizing OR processing, the microprocessor samples and evaluates both signals to determine if a contact closure has occurred (e.g., when the current meter has completed a revolution) and to distinguish an actual contact closure from external voltage discharges or spurious noise pulses. Upon verification of the occurrence of a contact closure, the microprocessor alerts the operator of that contact closure. Means are also provided for transmitting the information via FM band radio frequency to one or more appropriately tuned FM radios.