Abstract: A tape transport front panel is adjustable to position the controls conveniently for operators in various positions.

Abstract: An analog gate configuration employing multiple input transistors, eliminates distortion in its output signal when switching between multiple input signals during a corresponding switch-over interval when the input transistors are sharing current, by providing circuitry for sensing the occurrence of the switch-over interval. The sensing circuitry modulates a current source during the switch-over interval to selectively increase the current to be shared by the input transistors such that the current through each input transistor is maintained constant for any transistor which contributes to the output signal.

Abstract: Non-orthogonality of the blanking region information caused by the 25 Hz offset in a digital PAL-encoded color television signal is corrected by a dynamic offset circuit. To this end, a plurality of waveforms describing the envelopes of the blanking, sync and burst are stored, and during video signal processing are sequentially addressed at a 25 Hz rate. The resulting assembled output blanking information is orthogonal to the television scanning frequency.

Abstract: A latch for the pivoting head arm of a data-storage magnetic disc machine, in which a U-shaped latching member is arranged to avoid malfunctioning to block the movement of the arm, and may be operated entirely by means of a toggle spring, or entirely by means of a magnetic arrangement or cooperatively with both.

Abstract: A machine for extracting tape from a cassette and for threading the tape to a monoplanar disposition for longitudinal shuttling and transducing by fixed transducing heads, and then further threading the tape, if desired, to a helical disposition around a rotating head and scanning drum assembly without interrupting the longitudinal shuttling or transducing action.

Abstract: A method and apparatus is disclosed for recording and reproducing color television signals on a magnetic media such as magnetic tape, wherein the signals recorded on and reproduced from the magnetic media are in a digital domain. The analog color television signal is converted to digital signals in a manner whereby the horizontal blanking interval is compressed and digital synchronizing information is inserted in the compressed horizontal blanking interval for every line. Upon reproduction, the digital synchronizing information is extracted from the reproduced information and is provided to servo circuits for controlling the relative transport of the magnetic tape and operatively associated magnetic heads to effect synchronous reproduction of the recorded information relative to a reference signal.

Abstract: An improved reel servo for a recording and reproducing machine is disclosed. The reel servo as well as other servos in the machine are controlled by a single microprocessor which results in greater inherent communication between such servos and significantly improved operating capabilities. The reel servo itself is adapted to have the supply and take-up reels operate in different kinds of close loop servo control during various operating modes. The servo circuitry provides instantaneous information to the microprocessor for determining the diameter of tape that is wrapped on each of the reels. The reel servo has the capability of performing high speed shuttle and cueing operations without engaging the capstan and the tensioning arm can be positioned to provide the appropriate tape tension during shuttling in both the forward and reverse directions. An acceleration loop controls the supply reel so that the tape tension is maintained within predetermined upper and lower limits.

Abstract: A nonmagnetic holder is made having a plurality of precisely located parallel grooves. Each groove has a reference lateral surface provided therein. Individual magnetic transducers are inserted in each groove with a lateral surface abutting the reference lateral surface within that groove. The transducers are preferably made by well known batch fabrication techniques. A locating element, such as a leaf spring, is provided in each groove to urge the transducer core against the reference surface and to firmly hold the transducer in a desired position during alignment and assembly. The modular structure allows inspecting the individual transducers for mechanical or electrical damages and their replacement, if necessary, prior to the final assembly. The multichannel head is then integrally joined together, for example by bonding. The rejection rate of the resulting modular multichannel head is significantly reduced.

Abstract: The working surfaces of nickel-coated substrates for rigid magnetic discs are polished in a single-step process that employs a polishing composition comprising an aqueous suspension of unlubricated aluminum oxide powder having a hexagonal crystal shape and a nominal particle size of 1 to 10 microns, and colloidal aluminum oxide.

Abstract: In a disc information storage system which employs a servo data disc, a servo data head and a moveable carriage assembly for transporting a plurality of magnetic heads radially across the surface of the disc in response to a control signal produced in connection with a velocity command signal, an improved method and apparatus for production of a velocity command signal wherein one or a plurality of discrete velocity steps are added to the velocity command signal in a region which would otherwise indicate only a single value for velocity.

Abstract: A tape cassette has a springloaded indexing mechanism to urge the cassette reels in a tape winding directions so as to tension the free run of tape between the reels whenever the cassette is removed from the tape transport machine.

Abstract: A microprocessor controlled multiple servo system for use with a recording and reproducing apparatus is disclosed. The system controls all servo systems for a magnetic tape recording and reproducing apparatus, including a capstan servo, a reel servo, a scanning drum servo and an automatic scan tracking servo which controls the position of reproduced heads carried by the scanning drum which are of the type which can be transversely moved relative to the longitudinal direction of recorded tracks to accurately follow the tracks during special effect reproducing modes, such as slow motion, stop motion and fast motion reproducing. The microprocessor controlled servo system has unique and powerful functional capabilities which enable it to provide reliable precise asynchronous reproducing so that precisely accurate time compression and expansion can be carried out without performing any editing of the recorded material.

Abstract: A voltage controlled equalizer has two parallel signal paths. A first signal path is provided by a delay line coupled to an input of an amplifier. A control circuit is coupled between an input of the delay line and an output of the amplifier, via a second, parallel signal path. A control signal is applied to the control circuit to adjust the gain of the second signal path, thereby adjusting an amplitude versus frequency response characteristic of the equalizer. Signal delays caused by the control circuit are preferably selected substantially equal to those of the amplifier to compensate for undesired phase shifts of high frequency signals in the second signal path.

Abstract: A multiple speed servo is provided which measures and controls the speed of a head scanner below approximately 900 rpm, to maintain a preselected, relatively reduced, scanner speed which is fast enough to aid threading and unthreading tape about the scanner in the reverse direction, but not fast enough to damage the heads or tape. The safe handling is enhanced by selectively reducing the tape speed during reverse threading and unthreading of the tape, to maintain a preferred ratio of scanner circumferential velocity equal to, or slightly greater than, the tape speed. To this end, a slow speed scanner servo is employed to continually monitor and maintain the scanner at the preselected reduced scanner speed while the tape is maintained at the associated reduced tape speed.

Abstract: A system for spatially transforming images by separate transformation of each dimension of the image is exemplified by a raster scan television system which includes for each color component a transposing memory providing a change of scan direction from horizontal to vertical, a vertical transformation system transforming in the vertical direction the vertically scanned video information, a second transposing memory coupled to receive vertically transformed video information and provide a change of scan direction from vertical back to horizontal, and a horizontal transformation system coupled to horizontally transform the horizontally scanned video signal to produce a color component output signal.

Abstract: A narrow track magnetoresistive transducer has a square shaped bias permanent magnet superposed with an MR element. The square shaped magnet provides bias field components of substantially the same magnitude in both hard and easy axis directions of the MR element. A stable and uniform bias field is thereby obtained.

Abstract: Apparatus and method for phase scatter detection and reduction in a digital signal transmitted over a channel, for example a magnetic recording and reproducing channel. The transmitted signal is equalized to compensate for a non-constant amplitude response and/or non-linear phase response of the channel. A bit synchronization circuit, employing a controllable frequency reference clock signal generator and a digital phase detector, provides a reference clock synchronized with the transmitted data. The amount of phase scatter in the equalized signal is determined by monitoring the switching frequency of the phase detector. The equalizer may be adjusted to minimize that frequency, thereby reducing phase scatter.

Abstract: A transducer and method are described where track width reducing notches are filled with a nonmagnetic material which is heated to or slightly over its softening temperature but below its melting temperature. Concentrated high pressure at discrete locations is applied to the softened nonmagnetic material to enhance flow thereof into the notches.

Abstract: A tachometer assembly comprises two toothed rings (68, 70) in approximate axial register. The rings have similar peripheries of which the teeth (69, 71) are closely spaced in the axial direction of the rings. Magnetic flux in a path extending axially of the teeth varies as the rings rotate and is sensed by a coil (74) disposed coaxially of the rings.