An ultrasonic scanner includes an assembly mounted within a housing and pivoting between two positions. The assembly includes an ultrasonic module that generates an ultrasonic beam directed at a target, such a tissue and detecting the corresponding return beam. A worm screw with a block contacting the assembly is used to selectively pivot the assembly to a desired position. The worm screw is driven by a DC motor and the position of the assembly is monitored using a proximity sensor, such as a Hall Effect Device. A hybrid controller in one mode receives analog signals from the Hall Effect Device and uses them as a feedback signal to an analog OP AMP driving the DC motor to move said assembly to a predetermined position. In another embodiment, the motor is activated for a predetermined time to move the assembly by a predetermined amount.