Abstract: A remotely actuable boom assembly for floating and positioning a sonar transducer in otherwise inaccessible positions for fishermen. A rigid, supportive frame assembly adapted to be coupled in a desired position upon the side of a conventional fishing boat pivotally mounts an articulated, elongated boom assembly comprised of a pair of control arms which extend generally horizontally outwardly from the side of the boat. The arms are normally spring biased into a preferred operational orientation. The outermost control arm terminates in a housing which is floated upon the water. The suspension system dynamically compensates for wave action or movement during use of the apparatus. The floating housing mounts and controls an internally disposed sonar transducer which may be remotely pivoted by a cable to sweep or scan various regions under the water. A pair of levers associated with the frame enable remote control of the boom and the captivated sonar sensor.