Abstract: Apparatus is disclosed for issuing commands for controlling the operation of a transport mechanism preferably of the type which transports a recording medium such as a magnetic tape for the purpose of stopping at a predetermined cue point location on the medium. The apparatus includes a counter which accumulates tachometer pulses that are generated by movement of the medium so that the instantaneous count of the counter always provides an indication of the distance from the cue point location. Division rate outputs of the tachometer rate are provided by the counter and means responsive to various predetermined counts selects one of the division rate outputs for application to an error detector which measures the period of the division rate signal and provides an overspeed indication when the period exceeds a predetermined value. The determination of an overspeed condition results in a deceleration command signal being generated.

Abstract: A coring circuit located prior to the aperture corrector circuit provides fast acting, remotely controlled, temperature compensated, frequency selective coring of the video signal. The wideband video signal is separated into its low frequency and high frequency components. The high frequency component is transformer coupled to a coring means proper which cores out the corresponding high frequency noise. The cored high frequency component then is recombined with the low frequency component to reconstitute the cored composite video signal for subsequent application to the aperture correction circuit.

Abstract: A large, 2 wire, 2-1/2D core memory includes four, 1K (1024) by 1280, core frames with 1280 Y conductors each stringing and inductively coupling a column of 1024 cores in each of the four frames and 4K orthogonal X conductors each stringing and inductively coupling one row of 1280 cores. A word position within the memory is defined by 5 pairs of Y conductors, a corresponding X conductor from each frame, and selection of relative current directions in the Y conductors. Reading of a 20 bit word is accomplished with 5 sense amplifiers in four rapid succession read sub-operations. Digit sense conductor noise recovery time is minimized by arranging for balanced, predictable delta noise on each digit sense conductor of a pair and by providing a multiple digit sense conductor pair crossover arrangement which results in a balancing of image current coupling into adjacent digit sense conductor pairs.

Abstract: Lithium ferrites are sintered with a mixture of phosphorus pentoxide and vanadium pentoxide or bismuth trioxide to produce memory cores of high density and small grain size having high figures of merit. The lithium ferrites may contain additional ions such as zinc, nickel and manganese.

Abstract: A method and apparatus provide for the elimination of any net DC component from the transmission of binary data sequentially in successive clocked bit cells of a transmission channel wherein logical first bit states, e.g., 0's, are normally transmitted as signal transitions relatively early in respective bit cells, preferably at cell edge, and logical second bit states, e.g., 1's, are normally transmitted as signal transitions relatively late in respective bit cells, preferably at mid-cell, and any transition relatively early in a bit cell following a transition relatively late in the next preceding bit cell is suppressed.

Abstract: A professional audio tape transport capstan control system includes a single capstan continuously engaging a length of tape to provide bidirectional motion control in all modes of operation. A D.C. capstan drive motor is directly coupled to the capstan and energized for precise control over tape motion. A hybrid servo switches between digital position phase lock velocity control and analog constant acceleration control to provide both precise control over play speed and rapid acceleration. With acceleration to a stabilized play speed occurring in less than 0.5 sec an operator may treat the acceleration time as instantaneous for most applications.

Abstract: A recording medium transport control precisely controls the movement of a recording medium such as magnetic tape at a desired velocity. A pulse drive control adapted for manipulation provides drive pulses to the transport. Each drive pulse is of a variable duration sufficient to drive the transport so that the medium is moved a predetermined distance. One embodiment of the present invention includes a velocity servo drive control, also adapted for manipulation, for providing an adjustable continuous drive signal to the transport and a switch for switching control of the transport from the pulse drive control to the velocity servo drive control when the velocity of the transport reaches a predetermined cross-over velocity.

Abstract: In an apparatus for automatically maintaining a transducing head assembly on the proper track, which is particularly adapted for a helical scan recording and/or reproducing apparatus capable of providing special motion effects, track selection method and apparatus is disclosed. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. During the acceleration of the tape to normal speed, the tape transport is initially controlled relative to a recorded control track to position the head relative to the recorded tracks so that the reproduced video signal is color framed with respect to studio reference.

Abstract: Timing errors in a color television signal equal to a fraction of the nominal period of one cycle of color burst are corrected by clocking an analog-to-digital converter during each horizontal line interval of the television signal with two clock signals having the same nominal frequency equal to a multiple of that of the color burst. During the color burst interval of each horizontal line, the analog-to-digital converter is clocked by a stable time base reference clock signal and the obtained digitized color burst is stored in a recyclable digital memory. Following the color burst interval, the stored digitized color burst is regenerated for the remainder of the horizontal line and a clock signal derived for use in clocking the analog-to-digital converter.

Abstract: An audio signal is sampled, quantized and the values are stored in a specific digital data block/sub-block format on alternate tracks of a recording medium. The block/sub-block format provides an inherent simplification of error correction techniques, and consists of dividing the digital audio data into groups of digital words, and recording alternate words on separate tracks in the medium. Cyclic redundancy check characters, synchronization, and parity information are selectively interspersed with the data to define sub-blocks which in turn are combined into separate blocks of the block/sub-block arrangement. On reproduce, any errors, dropouts, etc., are detected and corrected or concealed to reconstitute the original audio signal. Editing is facilitated by the separated block arrangement which allows entering and exiting the record mode without destroying any data.

Abstract: A mount for holding and varying the position of a magnetic transducing head assembly comprises a pair of stiff but flexibly-hinged leaves arranged in a parallel-motion linkage. In application to a rotating head-mounting drum, the axis of each hinge is arranged to be parallel to the line of effective action of centrifugal force upon the movable portion of the mount, so as to neutralize the centrifugal force effect upon the movement of the linked leaves.

Abstract: Apparatus is disclosed for recording real time video information signals on magnetic media by sampling the information signal and converting the samples to a plurality of component digital data streams which are simultaneously recorded on separate surfaces of a single disc pack associated with a generally standard computer disc drive and for thereafter reproducing the plurality of digital data streams and recombining the same in a manner whereby the analog video information signal is reconstructed.

Abstract: A method and apparatus is disclosed for automatically maintaining a transducing head on the proper track and is particularly adapted for a helical scan recording and reproducing apparatus that is capable of providing special motion effects, such as slow, still and fast motion, and other effects. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. To provide accurate head tracking, a small oscillator motion (dither) is applied to the head to cause it to vibrate laterally between two limits relative to the track. This causes amplitude modulation of the reproduced signal, which is in the form of an RF envelope of frequency modulated carrier.

Abstract: A rotating transducing head drum that mounts a number of transducer heads for sweeping rotation across the surface of a record medium. The head mounts are either of the bimorph, i.e., laterally displaceable leaf type, or of a non-displaceable leaf type simulating the displaceable type; in either case the mounts are factory secured in substantially identical shoes and in precise predetermined dimensional relation to radially, axially and circumferentially facing gauge surfaces of the shoes. Mating gauge surfaces are factory formed on the drum. Thus, the heads with their shoes are interchangeable in the field without the need for field adjustments.

Abstract: Apparatus is disclosed for transmitting through a transmission channel a digital data stream of the type where the position of a level transition within a bit cell determines the information content of the bit cell. As the data stream is transmitted through the transmission channel, degradation of the transitions can occur due to differring response characteristics with respect to level transitions in opposite directions. A pulse for each level transition of the data stream is generated, the pulses converted to a pair of complementary level pulses for transmission, a single level pulse is produced from the transmitted complementary level pulses when the instantaneous level of both said complementary pulses are the same during a transition and thereafter an output signal is provided having a level transition for each pulse.

Abstract: Apparatus is disclosed for phase locking the output of a voltage controlled oscillator to a self-clocking data pulse stream occurring at a basic predetermined rate, the data stream being of the kind in which the data content is determined by a signal state change located in one of two positions within the data cell interval of the data stream. Each signal state change is defined by a narrow data pulse. The oscillator is controlled by a first means to operate at the predetermined rate when the data pulses are not present and by a second means when the data pulses are present. The second means compares one selected transition of the clock pulses of the oscillator output signal to the position of the data pulse and provides a variable control voltage to the oscillator to adjust its phase so that the the selected clock pulse transition is synchronized to occur at the midpoint of the data pulses.

Abstract: A tape reel container of the flat-walled box type holding a reel-supporting tray. The periphery of the tray is formed with a downward and outwardly facing step confronting the side walls of the container, and the side walls are formed with inward and downwardly folding flaps engaging the tray step, so as to both retain and be retained by the tray.

Abstract: A transducer core comprises a magnetic core superposed and integrally joined with a supporting composite body. The magnetic core has poles defining at least one nonmagnetic gap therebetween. The composite body has a nonmagnetic front portion spanning the nonmagnetic gap of the superposed magnetic core and a contiguous magnetic back portion. The superposed magnetic core and composite body are provided with overlapping grooves forming a window adapted to receive transducer windings.

Abstract: An improved drive circuitry for controlling the deflection of a bimorph comprising a pair of electrically poled piezo-ceramic elements bonded to a common substrate is disclosed which applies deflection voltage in a manner whereby the polarity is always in the poling direction of each of the elements so that depolarization of the piezo-ceramic elements does not occur. The circuitry applies a common polarity D. C. biasing voltage to both of the piezo-ceramic elements of the bimorph and also applies oppositely phased A. C. deflection signals to the respective piezo-ceramic elements.

Abstract: A large, 2 wire, 21/2D core memory includes four, 1K (1024) by 1280, core frames with 1280 Y conductors each stringing and inductively coupling a column of 1024 cores in each of the four frames and 4K orthogonal X conductors each stringing and inductively coupling one row of 1280 cores. A word position within the memory is defined by 5 pairs of Y conductors, a corresponding X conductor from each frame, and selection of relative current directions in the Y conductors. Reading of a 20 bit word is accomplished with 5 sense amplifiers in four rapid sucession read sub-operations. Writing is accomplished in two sub-operations by separately controlling partial select digit currents in each of the 5 pairs of Y conductors. A bidirectional X drive and switching arrangement utilizes overlapping X drive currents and shared circuitry to maximize memory speed and reduce electronic components costs.