Abstract: A magnetic bubble memory detector-amplifier for use with a bubble memory device having the dual output from an active and a dummy bubble detector in combination consists of a differential amplifier associated with constant current sources to drive the bubble detector elements, a notch filter coupled to the output of the differential amplifier to eliminate the rotating magnetic field frequency component, an amplifier coupled to the output of the filter which is controlled by a bias pulse at the fundamental frequency of operation to provide a reference for better discrimination between "ones" and "zeros," and, finally, a self-biasing detector coupled with a strobed output flip-flop.

Abstract: In a field access type bubble memory system using a major loop minor loop organization, additional redundant minor loops are included in each memory device so that defective minor loops may be disregarded and the memory retain its nominal capacity. Thus, the total number of minor loops is in excess of the nominal capacity. A stationary register is formed integrally with the major loop by coupling bubble idlers directly to the major loop bubble propagation path. The stationary register has as many register positions as the total number of minor loops coupled to the major loop. An appropriate binary code identifies in the appropriate register location the corresponding minor loop which is defective, including nominally defective minor loops, if necessary, so that a number of minor loops equal to the nominal capacity of the memory are identified as good.

Abstract: A noncirculating register for bubble memory systems is comprised of a propagation track, or shift register, which allows the transmission of bubbles in a serial path, a plurality of bubble idlers formed in an array parallel and adjacent to the propagation track and coupled thereto and a single current conductor arranged in such a fashion that there is a loop formed in the vicinity of each idler location, said loop extending into the propagation track which contains the normal straight line path of the conductor. By properly current pulsing the conductor loop in proper relationship to the rotating in-plane magnetic field, bubbles may be transferred in, transferred out, replicated out or annihilated in the various idler locations with respect to the contents of the propagation track. Without a current pulse, the contents of the idler locations and the propagation track have no effect on one another.

Abstract: In a magnetic bubble memory device, an improvement to the means for providing an in-plane rotational magnetic field to advance bubbles through some appropriate, staged structural form of permalloy elements is a conductor overlay positioned so that the permalloy elements are generally oriented normally to current flow in the conductors. The conductor overlay may consist of two orthogonal groups of parallel wires or a single grid or mesh of wires with four electrical connections, one on each of four edges. The conductor overlay may be driven to produce an in-plane rotating magnetic field and the magnetic bubbles travel to or follow the induced poles in the permalloy elements just as if conventionally driven.

Abstract: A bubble memory package is comprised of a nonmagnetizable heat sink formed with a pocket for receiving the field coil and magnetic chip carrier assemblies. The heat sink is massive and capable of dissipating the heat generated by a high density memory operating at a high frequency. The heat sink is not closed over the top of the coil and memory carrier assemblies to reduce eddy and circulating electrical currents formed in an electrically conductive heat sink. The heat sink is formed with a track guide for receiving a heat sink plate which may be of electrically nonconductive material but which has sufficient heat conductivity to assist in transferring heat into the heat sink. The top of the heat sink plate is formed with a pocket for receiving a permanent magnet to generate the bias field and the bottom of the heat sink is formed with a second pocket for receiving a magnet assembly. The entire package is surrounded by a magnetic shield container.

Abstract: A computer interface for interconnecting a plurality of computer modules in a multiplex manner to emulate a computer configuration includes transmitters and receivers associated with each master and slave module, together with logic means whereby the master module is permitted to initiate computer operations with acknowledgement from the slave to insure proper data speeds. Conflicts are resolved between master modules.

Abstract: In a field access type bubble memory system using a major loop-minor loop organization, additional redundant minor loops are included in each memory chip so that defective minor loops may be discarded and the memory retain its nominal capacity. Thus, the total number of minor loops is in excess of the nominal capacity. A stationary register is placed adjacent to and parallel to a major loop and has as many register positions as the total number of minor loops on the chip. An appropriate binary code identifies in the appropriate register location the corresponding minor loop which is defective, including nominally defective minor loops, if necessary, so that a number of minor loops equal to the nominal capacity of the memory are identified as good. Each time the memory is accessed, the contents of the register are accessed, nondestructively, and read into and merged with the contents of the major loop on an every other one basis.

Abstract: An electron beam tube electrostatic deflection system and method of operation is described. The electron beam tube includes an eight-fold deflector and means are provided for applying two different quadrupole correction electric potentials to selected ones of the eight-fold deflector members and for applying an octupole correction electrical potential to all eight deflector members. In the preferred embodiment, the quadrupole and octupole correction potentials applied to one set of four deflector members are represented by the respective values (V.sub.2c - V), (-V.sub.2c - V), (V.sub.2c - V) and (-V.sub.2c - V), and the quadrupole and octupole correction potentials applied to the second set of four deflector members are represented respectively by the values (V.sub.2s + V), (-V.sub.2s + V), (V.sub.2s + V) and (-V.sub.2s + V) where the quadrupole correction electric potentialV.sub.2c = [A.sub.2c (V.sub.x.sup.2 - V.sub.y.sup.2)]/V.sub.c, (1)the quadrupole correction electric potentialV.sub.2s = (2A.sub.2s V.

Abstract: A logic system is disclosed for using a memory device of the serial read type having redundant elements in excess of the nominal memory size and consists of a Programmable Read Only Memory having a defect map programmed into it with respect to the associated memory device, a shift register of a predetermined length equivalent to the maximum number of allowable defects, a multiplexer associated with the shift register, a position counter for controlling the multiplexer and, finally, appropriate logic to control the system. This system is disclosed in connection with a bubble memory system of the field access major loop -- minor loop type having extra minor loops. As defects are encountered in writing, data is shifted through the shift register while the multiplexer is incremented to the proper output position of the shift register based on the number of encountered defects. As data is read, an analogous reverse to writing operation is performed with the multiplexer being decremented.

Abstract: A data recording and readback subsystem for digital computer systems employing random access electron beam memories having an electron beam write/read apparatus for recording data to be stored on a recording member that is subject to fatigue in the eventuality of excessive write/read storage operations at any given physical location on the recording member. The improved method and apparatus for data management comprising systematically permuting the physical location of data stored on the recording member, recording each permutation of the data, deriving signals representative of the number of permutation operations, and combining programmer initiated requests from the computer system central processing unit for data stored in the electron beam memory with the signals representative of the number of permutations to derive an actual physical address signal for application to the electron beam memory for recovery of the requested data.

Abstract: A magnetic orientation sensor for magnetic recording media includes a transducer that writes a magnetic pattern on the recording medium and then reads it back. The reading is taken a number of times at a given location but with the magnetic flux traveling in various directions. The strength of the readback signal is used to interpret the magnetic properties of the medium, in particular a direction of orientation which is the preferred or strongest magnetic conductor. The transducer and the medium are stationary with respect to one another at each measurement. The transducer or magnetic head consists of a circular or ring-type structure having a rotating center spindle having a longitudinal bar of magnetic conductive material on the face thereof to create a magnetic field of varying orientation during the writing and reading process.

Abstract: A grid system for an ion beam generator is provided having a frustoconical shape so that the collimated ion beam converges at a predetermined angle toward the target to provide selective beveled etching.

Abstract: A method for forming a flat, thin polyester film into a curved film using heat, peripheral support for the film, and a single die.

Abstract: In a conventional disk drive device using concentric servo tracks to operate data heads on concentric data tracks, a second mode of operation is provided which is compatible with the use of concentric servo tracks for driving the data heads in a spiral, continuous mode for accessing all of the data on a particular disk surface in a single data read or data write operation. A conventional computer system disk drive could be modified for occasional use in storing and retransmission of video signals. In the preferred embodiment of the invention, each servo track is provided with a once per revolution clock pulse which starts the operation of an integrator. The integrator generates a time varying signal of the same period as the time for one revolution of the disk pack. An error signal is generated by conventional means to indicate the error in position of the servo tracking head with respect to the servo track.

Abstract: A current drive circuit for deriving a triangular current waveform for driving an inductive load, such as the field coils of a bubble memory, comprises a series of at least four diodes connected between the positive and negative input voltage lines. A pair of switching devices, such as switching transistors, are connected in series such that each switching device is in parallel with two of the diodes. The junction between the switching devices is also connected to one output for the inductive load. The intermediate diodes are connected together and to one side of a time delay circuit, the opposite side of which is connected to the second output for the opposite side of the inductive load. A modification of the invention comprises a second diode and switching circuit connected between the time delay circuit and the second output.

Abstract: A wide band monopulse antenna includes a plurality of contiguous square quad-ridged waveguides arranged in a geometric array. Proper orientation of the array permits connection to circuitry to permit use of the individual waveguides for development of azimuth, elevation and sum pattern signals. Further, orientation of concentric arrays permits extension of the frequency band.

Abstract: The present invention shows a plasma display panel drive circuit using low voltage controlled self-actuating devices as clamp circuits for selection of drive lines to be driven. Since such clamp circuits are in a normally ON condition for the sustain mode, the clamp circuits are self-actuating to transmit sustain pulses. The clamp circuits must be selected OFF to prevent the transmission of write and erase pulses in a self-actuating mode to the selected drive electrodes so that only the desired drive electrodes receive write and erase pulses.

Abstract: A structure for supporting a particular type of plasma display panel. The panel is of the type formed of two flat rectangular plates attached to each other face to face with crossed longitudinal axes, the active panel area comprising the face to face surfaces. Support bars with resilient gaskets interposed between themselves and the two plates provide a shock-resistant mounting. Electronic circuitry can be attached to the support bars to provide a compact package with electronic circuitry adjacent to and substantially coplanar with the panel itself.

Abstract: A location sensitive touch panel for use on a rigid substrate. The substrate carries a first set of conductive strips. A resilient plastic membrane overlaying it carries a second set of conductive strips orthogonal to and spaced from the first set. Finger pressure can cause electrical contact between any one of the first set of strips and any one of the second set of strips. The substrate may be either flat or curved, with the membrane conforming to its contour.