Abstract: There is disclosed a low power motor and brake assembly for a magnetic tape reel of a magnetic tape recorder/player. The magnetic tape reel is driven by a motor having a rotor fixed to the reel shaft and a stator which is rotatably mounted. A brake assembly includes a brake drum mounted on the reel shaft and a spring loaded brake band engaging the brake drum. One end of the brake band is attached to the stator by a linkage. When the motor is energized, the stator rotates and releases the brake band from the drum by means of rotation of the linkage.

Abstract: A resistor has a resistance which is precisely controlled by means of a voltage control circuit. The controlled resistor is a radiation sensitive device which is optically coupled to a source of radiation connected to the output of an operational amplifier. A control circuit applies a controllable (preferably programmable) voltage, functionally related to a desired resistance of the controlled resistor, to the input of the operational amplifier. Also connected to the input of the operational amplifier is a feedback radiation sensitive resistor, which is also optically coupled to the radiation source. Preferably, the controlled radiation sensitive resistor and the feedback radiation sensitive resistor have substantially identical resistance characteristics. A compensation circuit is electrically connected between the input and output of the operational amplifier.

Abstract: In magnetic tape recording apparatus a magnetic tape reel is clamped to a spindle apparatus so that vibration between the spindle apparatus and reel is minimized and so that the reel is operable free of contact with a reel container. A magnetic tape reel having a central opening extending from a face of the reel and, within the opening, a plurality of reel projections with inner radial surfaces spaced from the reel face, is clamped to a tubular spindle member by means of a reel clamping member rotatably mounted at the end of the spindle member. The reel clamping member is actuated by a control member which is slidably mounted within the spindle member.

Abstract: In a system mounting a transducer on the end of a frame for sweeping motion displacement laterally to a track on a record surface, the frame has arms connected to a fixed support. The frame may include a torsion member connected to a driver for rotation therewith and a rigid member rigidly connected to the free ends of the arms causing the frame arms to form an "S" shaped curve. The transducer is connected to a mounting member rigidly connected to the free end of the frame. The frame causes the transducer to remain in an orientation at a selected angle to the record surface.

Abstract: A reel assembly apparatus for coaxial magnetic tape reels is provided in which both an inboard reel and an outboard reel may be reliably clamped to their respective drive spindles from the outboard side of the assembly apparatus with ease and convenience. For the purpose of clamping the inboard reel, an internal locking nut extends radially in the plane of the inboard reel from its drive spindle into threading engagement with a hub of the inboard reel. A linkage, extending axially through the outboard drive spindle, rotates in response to turning movement of a bail accessible to an operator. The locking nut, in response to the rotation of the linkage, (1) initially causes the inboard hub to rotate, relative to the inboard reel, a limited amount into a reel-clamping position, and (2) then causes an axial movement of the inboard hub. This latter movement drives the inboard reel axially, to clamp it against a radially extending member of the inboard drive spindle.

Abstract: Tracking control apparatus for a magnetic storage device is provided for playback of information recorded on tracks at alternating azimuth angles which correspond to mutually different azimuth angles of a pair of magnetic playback heads. The playback heads have track-wise widths which are less than the width of their associated record tracks, to prevent the attenuation of their playback signals resulting from limited playback head tracking error. A tracking control head, which has an azimuth angle of one of the playback heads, is mounted for selectively overlapping adjacent record tracks in accordance with the magnitude and direction of the tracking error of the playback heads. Signal comparison circuitry produces a tracking error signal in accordance with the difference between the output of the control head and the output of a playback head.