Abstract: A video display terminal is provided with controls which permit independent adjustment of the background information and the foreground information. Each control comprises an adjustable constant current source connected to one of two branches of a differential amplifier. One branch of the differential amplifier is employed to control the background intensity and the other branch of the differential amplifier is employed to control the foreground intensity.

Abstract: A method and apparatus for performing high speed graphics fill is provided. Any closed line geometric shape or polygon that can be defined by pixel position is stored in memory. The memory pixel positions are stored in address locations corresponding to row and column positions. A first sequential examination of the data is made in reverse raster scan order to make a preliminary determination of the pixel positions inside the closed polygon. A second sequential examination of the data is made in forward or regular raster scan order and a final determination is made whether the pixel positions are inside the polygon and shall be filled. The final determination of pixel positions to be filled is stored shortly before the graphics fill operation is performed so that the fill operation is performed in raster scan time at high speed.

Abstract: Transmitting and receiving apparatus for transmitting data includes a purged code encoder at the transmitter for encoding digital data into constant weight unbalanced codewords representative of the digital data. The constant weight unbalanced codewords containing error correction bits are preferably transmitted as balanced codewords and are decoded at the receiver employing Golay decoders or algebraic decoders to recover the original digital data without the requirement of a large number of matched filter previously employed for decoding.

Abstract: A lockable compliant end effector apparatus is useful with a robotic arm for the automated assembly of electronic equipment. The end effector includes a main body portion having first and second ends. A socket is formed in the first end. A first fluid passageway connects the socket with the second end of the main body portion. A member is mounted for multi-directional movement in the socket. The member is retainable in a stationary position relative to the socket and has a second fluid passageway formed therethrough. The second passageway has a first end adjacent the first passageway and a second end adjacent the first end of the main body. A sealing member is connected to the mounted member adjacent the second end of the second passageway. The end effector retains an electronic component in original orientation from a pickup point to an insertion point.

Abstract: A method and apparatus of offset correction which can be applied to control systems, primarily phase-locked-loop systems, and which permits sampling of the error signals for use as an auxiliary input to the system in order to center the error signal around zero.

Abstract: The problem of re-establishment of initial precision registration of end-effectors used in automatic robotic assembly following failed insertion attempts is avoided due to a positive registration compliant apparatus having a support member including a bearing mount spaced apart from a shaped seat. A holder for holding and mounting electronic components is movably mounted on the support member and extends through the bearing mount. The holder has a portion correspondingly shaped for mating engagement with the shaped seat. The holder is resiliently urged into engagement with the seat. A rotation limiter is provided for limiting rotation of the holder relative to the support.

Abstract: A video display control circuit, for an intelligent terminal, includes a large cost efficient Random-Access Memory (RAM). A portion of the RAM memory is utilized as a high speed character generator instead of employing a dedicated Read Only Memory (ROM). Novel timing and memory control circuits are provided which permit characters to be generated witout any delay or change of real character timing. The characters in RAM may be modified or changed which is not possible with dedicated Read Only Memories.

Abstract: A novel high speed gallium arsenide depletion mode field effect transistor logic circuit is provided. One logic input is connected to the source electrode of the switching transistor and draws current when a low level input voltage is provided. Other logic inputs are connected to the gate electrode of the switching transistor and supplies current when a high or low level input voltage is provided. The novel logic output from the source electrode of the switching transistor is a complex OR function which may be employed for a logic family having fewer stages of logic than prior art gallium arsenide circuits.

Abstract: An apparatus for maintaining electronic component pin alignment includes a support member having an adjacent lead shear, a stationary nest, a printed circuit board and a component feeder. A component in the component feeder includes a chip having a plurality of leads. The leads have a first end connected to the chip and a second free end. A movable lead guide engages the first end of the leads. A robot is mounted adjacent the support member for picking up the component from the component feeder, inserting the component into the stationary nest moving the component relative to the stationary nest for moving the lead guide from the first end of the leads toward the second free end of the leads, moving the component from the stationary nest to the shear for shearing the second free end of the leads, and moving the component from the shear to the printed circuit board and urging the leads into corresponding holes formed in the printed circuit board.

Abstract: A novel maximum likelihood sequence detector is provided for decoding linear cyclic error correction codes. The detector comprises one cyclic correlator for each two shaft sets of the code which have weights greater than one, and a serial correlator for detecting the shift sets of all zero's and all one's. The number of cyclic correlators required to decode linear codes is reduced to less than half the number of shift sets which define all the codewords instead of half the number of codewords where the number of shift sets is always less than the number of codewords.

Abstract: A disc is firmly clamped to the end of a rotatable spindle by a coaxial clamping plate spaced from the spindle end by a ring between the plate and disc surface and attached to the spindle by a single coaxial bolt. The flexible plate, thicker at its center than near its periphery, has a substantially flat inner surface which, when stressed by tightening of the bolt, is deformed without exceeding its yield stress to the point where its center section contacts the spindle end surface to provide a constant predetermined clamping force evenly around the disc.The disc and spindle assembly is rapidly and accurately balanced without loosening the clamped disc from the spindle with an adjustable balancing bar which is attached to the head of the coaxial bolt and which may be properly adjusted by the use of a conventional balancing system which can indicate magnitude and direction of the imbalance.

Abstract: A high gain Josephson junction logic circuit is provided. The novel circuit comprises a high gain non-linear threshold input Josephson junction logic circuit which is coupled to a high gain Josephson junction amplifier. The high gain input circuit provides the capability of driving a larger number of output circuits or employing a larger number of input signals.

Abstract: An integrated circuit chip is cooled by being mounted on a substrate which is urged into contact with a compliant mat which includes a layer having a predetermined array of interconnected metallic pads for spreading heat flux more uniformly. The mat is connected to a plate which may be water cooled. The mat also includes additional layers which are heat conductive and electrically insulative. One of the additional layers is a film of paste.

Abstract: During the assembly of electronic components on circuit boards, the problems of ductile smear cusps produced on wire ends by traditional scissor-type shearing are addressed by a spiral orbital shear apparatus. This apparatus includes a first fixed plate having an array of apertures and a second plate also having the array of apertures. The first and second plates have abutting surfaces. A first eccentric drive member is connected to rotate at a first rate in a first direction. A second eccentric drive member is connected to the second plate and rotates with the first eccentric drive member. The second drive member is also rotated at a second rate in the first direction independently of the rotation of the first drive member.

Abstract: Circuitry for distinguishing each value in a read signal magnetically recorded in ternary-3 position modulation in which the values 1, 2 and 0 are detected and equalized into a singlet, a doublet and absence of magnetic flux change. The circuitry first determines the position locations of each singlet peak and doublet crossover point to establish proper timing of the output signals and then identifies the particular type of signal appearing at the timing points in the read signal sequence. Singlets are identified by the much greater amplitudes in the integrated read signal. Doublets are identified as waveforms having slopes at zero crossovers that correspond in polarity to that of the previous singlet. A novel detector circuit is provided that can correctly identify doublets in a code sequence, irrespective of the presence of a previous singlet, when a recording rule is followed that includes the insertion of a number of consecutive ternary 0 symbols into the recorded signal.

Abstract: Apparatus for producing a circular-queue structure which permits interfacing between a high speed mini-computer and a relatively slow speed microprocessor via a common memory and with multi-device, asynchronous handling capability. The structure also permits commands and data to be chained in the same queue. The apparatus permits multiple devices to be handled simultaneously. By monitoring the memory address which is being accessed by the minicomputer, the information retrieved from the memory by the microprocessor is selectively validated or invalidated.

Abstract: A novel multilayer lift-off pattern of positive and negative photoresist materials is provided. A positive first layer is deposited on a substrate and flood exposed before a subsequent layer of negative photoresist material is added on top of the positive photoresist material. An optional third layer of positive photoresist material may be added on top of the negative photoresist to provide the top layer. A window or aperture is provided in the top layer employing conventional mask, exposure and development techniques. The top of the bottom layer is plasma etched through the window or aperture so that the previously flood exposed bottom layer can be developed without affecting the layers deposited thereon. A deep undercut lift-off pattern is provided which is useful in the manufacture of Josephson junction devices employing low temperature metals as well as for the manufacture of semiconductor devices.

Abstract: This invention is a device to reduce the wobble of a rotating shaft disposed in a cavity of a housing which wobble results from a spurious or undesirable positioning of a bearing assembly in which the shaft rotates. The present device includes a bearing follower which is shaped to have a long side which is in abutment with the side walls of the cavity. Accordingly, the follower cannot be readily placed in a cocked or misaligned position. The follower is spring loaded against the bearing assembly which is subject to being cocked and thereby reduces the capability of that bearing assembly to be misaligned.

Abstract: A unique memory management system for use with a memory device which is common (or shared) with a plurality of user elements utilizing a memory address counter, scratch pad address memory, external memory address inputs and an address multiplexer.

Abstract: A programmable force assembler for robots includes a bi-directionally actuatable slide member. A microprocessor is programmable for controlling insertion force independent of the distance moved by the slide member. A position indicator transmits slide member distance signals and velocity information to the microprocessor. A pressure transducer is connected to the bi-directional actuator and is coupled to send signals to the microprocessor. A supply valve is connected to the bi-directional actuator and is coupled for receiving signals from the microprocessor in response to the pressure transducer signals.