Abstract: An electric motor, particularly for driving a gramophone, a tape recorder or an electric instrument at a low rotational speed whereby an induction effect is utilized to achieve good starting torque and a reluctance effect to give good torque when the motor is locked in and running synchronously. The motor includes a stator assembly with a first plurality of pairs of primary pole pieces each pair constituted by a first metal part for the energization by an in-phase current and a second plurality of pairs of primary pole pieces each pair constituted by a second metal part for energization by an out of phase current. The respective parts also define slots constituting secondary pole pieces.

Abstract: This invention relates to arrangements for use in controlling the movement of a pivoted arm and it has particular, though not exclusive, application in controlling the movement of a phonograph pick-up arm.

Abstract: An electrical circuit for use in controlling the coupling between two separate channels including a first transistor for connection in a first channel, a second transistor for connection in a second channel, a first and a second electrode of each transistor being connected in a respective output signal current carrying path, first signal coupling means connected between the said two first electrodes and second signal coupling means connected between the said two second electrodes, one of the said signal coupling means being variable.

Abstract: A linear bearing arrangement has a slider which slides in a channel in a slide and a layer of magnetic lubricant material which adheres to a magnetized region or regions of the slide, slider or both.

Abstract: A mechanical gearing with a first rotatable member, three spherical balls in contact with and rotated by the first member, a second relatively flexible member in contact with the balls and a third rigid member fixed with respect to the second member and against which the second member is urged by the balls so that the second and third members rotate with respect to each other.

Abstract: Method and apparatus for accurately controlling the position of a first member such as a phonograph stylus relative to a second movable member on which it is carried.

Abstract: A tone arm for a record player having a mirror at one end is provided. Opposite the mirror are a light source and two detector elements. When the tone are pivots from a desired angle light from the source is reflected upon the element more than on the other. The mirror is convexly curved so that pivotal motions of the tone arm in one plane will not affect the amount of light reaching the detectors.

Abstract: A bearing arrangement for a spindle including a bush having tapered ends and members having internally tapered surfaces arranged to cooperate with the tapered ends, and means to clamp the members towards one another upon the bush to support a spindle passing through the bush.

Abstract: An arrangement for use in indicating the speed of rotation of a body including a switch operated by elements which rotate according to the rotation of the body, a frequency generator which has an output signal at a frequency related to the desired speed of rotation of the body and an indicator which is actuated in accordance with the signals from both the switch and the frequency generator.

Abstract: The vertical movement of a phonograph pick-up arm is controlled magnetically or electro-magnetically by means including a body of magnetic material attached to the arm and magnetic field producing means arranged to exert a force on the body.

Abstract: A combination of a turntable for playing phonograph records, a lid covering the turntable, tone arm for tracking record grooves, and a cleaning element mounted on the lid for movement into contact with a constant annular area on the top side of the record for cleaning. A counterbalance weight controls the pressure of the cleaning element upon the record.

Abstract: The presence and size of a recorded disc on a turntable is detected and indicated by the interruption of a beam or beams of energy which passes in the plane of the disc, through a hole or holes in a turntable, or beneath the turntable.