Abstract: A method and apparatus is provided for controlling rotation of an ultrasound transducer. In accordance with the method of the present invention, a user-operable actuator that is movable over a continuous range of positions and generates a first signal representing the position of the actuator is provided. The method includes the steps of transforming the first signal into a second signal representing a desired velocity. Preferably, the second signal is a nonlinear transform of the first signal. The method further provides for rotating the ultrasound transducer in accordance with the second signal. In accordance with the apparatus of the present invention, a probe having a control housing, an actuator that may be manually positioned within a range of positions, and a transducer housing coupled to the control housing, which transducer housing contains an ultrasound transducer that is rotatably mounted for scanning a plurality of planes in a body, is disclosed.

Abstract: An apparatus and method for automatically controlling rotation of a transducer that is mechanically coupled to a motor are disclosed. The apparatus includes a motor controller coupled to the motor and a microprocessor. The motor controller includes a state-machine and an encoder. The microprocessor is coupled to the state-machine. Two methods for automatically controlling rotation of an ultrasound transducer are disclosed. The first method includes the steps of providing a microprocessor coupled to a motor controller, the motor controller comprising a state-machine and a speed setting circuit, and initializing the state-machine by providing a desired speed and a target position from the microprocessor. The first method further includes the step of automatically selecting the desired speed from the speed setting circuit in accordance with the initialized state-machine. The first method further includes rotating the ultrasound transducer at the selected speed.

Abstract: A series resonant power supply is switched at a constant frequency above the audio range, in which a magnetic amplifier is used to control the magnitude of the output voltage. It can be run silently, while providing high power at relatively low cost. The power supply includes a full or half bridge rectifying circuit with first and second common terminals. A magnetic amplifier is coupled from the first common terminal to a second common terminal. The magnetic amplifier includes a first primary coil for conducting current from the first common terminal to the second terminal. A secondary coil for generating an output current, and a control coil receiving a control current are coupled with the first primary coil. A second primary coil is connected to conduct current from the second common terminal to the first common terminal. A second secondary coil and a second control coil are coupled with the second primary coil.