Abstract: An improved linear actuator for reciprocating a read/write head mechanism relative to magnetic disk storage system is disclosed, including a second, supplemental solenoid coil and associated magnet means in addition to the usual arrangement, and by way of improving linearity and efficiency.

Abstract: A method for measuring bit shift, timing asymmetry and other characteristics indicative of the performance of a magnetic storage system, particularly for a system employing a thin-film magnetic head. In a preferred embodiment, complementary patterns are written many times around a circular track of a magnetic disk, each pattern including relatively closely spaced magnetic transitions as well as relatively widely spaced magnetic transitions. The relatively widely spaced transitions are chosen so as to be substantially unaffected by any other transitions. Measurements are made with reference to these widely spaced transitions and averaged for the many patterns recorded in the track so as to rapidly provide highly reliable measurements indicative of system performance.

Abstract: Disclosed is a heat sink for cooling an integrated circuit package. The heat sink comprises a single thin sheet of material having two oppositely facing major surfaces. These two major surfaces have a common perimeter defining a plurality of spaced-apart finger-shaped portions of the thin sheet of material that extend radially from a central portion of the sheet. The central portion is convex for attachment to the integrated circuit package; and the finger-shaped portions are formed to extend out of the plane of the central portion to become cooling fins for the central portion.

Abstract: A circuit having reduced susceptibility to noise includes a plurality of drivers coupled to a current bus; each driver receives a logic signal on a control terminal and operates to pass a large current when the logic signal is a one and pass a small current when the logic signal is a zero; the current bus has a parasitic inductance which generates a noise signal when the logic signals switch; noise on the current bus is parasitically coupled to the control terminal of each driver; and a plurality of noise reducing modules respectively couple to the control terminal of each driver and a common bus. Each module that receives a switching logic signal generates a control signal on the common bus that is similar in shape and opposite in polarity to the noise signal; and each module that does not receive a switching logic signal couples the control signal from the common bus to the control terminal to which it is connected.

Abstract: A heat exchange attachment device for integrated circuits is presented which eliminates any need for contact with adhesive pastes or solder. A snap-on holding piece permits a finned cooling unit to be threaded through an aluminum base plate attached to the pin grid array package so that a threaded shaft of the cooling unit may be screwed into adjustable contact with a beryllium oxide disk mounted on the integrated circuit package.

Abstract: The present disclosure describes a tool for correcting an otherwise rejectable pigtail in the last turn of a wrapped wire connection--the latter turn being oriented orthogonally to the longitudinal axis of the wrapping post but being displaced therefrom by a distance in excess of that permitted by quality control standards. The present tool is adapted to be inserted over the post and includes a cylindrical finger-like projection. Rotation of the tool by an operator causes the projection to engage the pigtail and to wipe it down toward the surface of the wiring post, thereby bringing it within acceptable tolerances.

Abstract: A printer system is configured as a kit for retrofitting the input consoles of existing letter sorting machines of the type used by the U.S. Postal Service. Such machines require that an operator, stationed at a console, enter sorting information for each mail piece, by way of a manually actuated keyboard. The present invention expands the processing capabilities of the machines by imprinting machine-readable, coded information on the respective faces of the mail pieces simultaneously with the sorting thereof. At the same time, the printing function does not impair or modify the usual operator-controlled console when mail is processed which does not require such coding.

Abstract: Improved flexible disk pack magnetic storage systems and associated elements are illustrated as adapted for pneumatic partitioning and indicate, among other features, the use of spacer segments in the gap between adjacent flexible disks these being pre-attached to each disk to isolate the axial pressurized air streams from non-selected gaps and also to provide a reference surface for registration of the disks in the course of compressing the stack together.

Abstract: A lock/ejector assembly device for attachment to a printed wiring board. Attachment of an upper and lower such assembly device to a printed wiring board provides locking pressure for stably fixing the printed wiring board into a rack which holds the mother board and its multiple interconnection contacts. A finger-movable snap lock in the assembly provides a "locking" function to fixate the board, or an "unlocking" function to permit removal of the board.

Abstract: A data transfer system for transferring data from magnetic tape peripheral units to a peripheral-controller for temporary storage and subsequent transfer to a host computer. A tape control unit, connected to the magnetic tape peripheral units, provides clock signals to a synchronization logic circuit which controls the transfer of data through two sequential latching registers to a buffer memory in the peripheral-controller. The two sequential latching registers function as a buffering delay element together with an automatic read logic unit which allows the read logic unit to use a lesser number of cycle-steal times than would ordinarily be required, while still controlling a steady uninterrupted flow of data words.

Abstract: A guillotine assembly is provided wherein a blade is insertable between two halves of an anvil to cut a paper web. The blade is provided with teeth which engage triangular grooves in a resilient member of the anvil which is pressed against a rigid anvil plate. Points on the teeth first penetrate the web. Thereafter, tooth mid-sections form a series of slits in the web. Thereafter, points of contiguity between the teeth jam the slits to sever the web. The teeth each enter one of the grooves in the resilient member for the points of contiguity to engage and displace the resilient member in the final stage of cutting.

Abstract: A method of sending self-clocking data characters and control characters in a sequence from a first communications node to a second node includes the steps of: encoding each data character as respective code pairs of the form 0XX . . . X1 and 1XX . . . X0 where the X's are the zero and one bits of the data character; encoding each control character as respective code pairs of the form 0XX . . . X0 and 1XX . . . X1 where again the X's are the zero and one bits of the control character; and transmitting, for each character in said sequence, the particular code in that character's code pair whose first code bit is the opposite of the last code bit of the immediately preceding character in the sequence.

Abstract: The present invention describes a tester for determining the value of unknown delay lines in the nanosecond and subnanosecond range. The unknown delay line is introduced into the circuit loop of a free-running square wave oscillator previously calibrated to a predetermined frequency. A change in oscillator frequency occurs which is a measure of the value of the delay introduced into the loop by the unknown line. Such delay may be calculated as a function of the calibration and delay line-measured frequencies. The present tester provides measurements with increased accuracy and rapidity over previous measuring techniques.

Abstract: A peripheral-controller (designated as a data-link-processor) manages data transfers between a main host computer and a magnetic tape peripheral unit. The peripheral-controller uses a common front end providing an instruction sequencing unit and a buffer memory to store data-in-transit in six blocks of 256 words each. A peripheral-dependent circuit unit of the peripheral-controller can provide automatic read or automatic write data transfers between the buffer memory and the magnetic tape peripheral unit without further attention from said instruction sequencing unit.

Abstract: A single-ended transformer drive circuit includes a transformer having a primary winding and a secondary winding and a switching transistor connected to the primary winding of the transformer and adapted to turn on and drive the transformer in the forward direction along its hysteresis curve, whereby an output voltage is generated in the secondary circuit of the transformer. An auxiliary transistor circuit is coupled to the transformer for driving it in the reverse direction along its hysteresis curve when the switching transistor turns off, whereby the transformer is reset and prepared for the next cycle of operation when the switching transistor turns on again.

Abstract: Silicon films in integrated circuits are mass produced with reduced structural defects by passing a reactant gas which contains silicon over a batch of wafers in a quartz chamber to deposit a silicon substance on both the wafers in a quartz chamber and the quartz walls of the chamber; repeating the passing step on other batches of wafers until the thickness of the silicon substance on the quartz walls exceeds a predetermined limit; directing a forceful stream of gas against the quartz walls to knock microscopic particles of the silicon substance therefrom; removing the knocked-off microscopic particles from the chamber; and continuing the passing and repeating steps with no intervening acid etch of the silicon substance on the quartz walls.

Abstract: An allocator for a reduction processor which evaluates programs stored as binary graphs employing variable-free applicative language codes. These graphs are made up of nodes, each of which exists in memory and contains as its most significant bit a mark bit which when set indicates that the node is being used in a graph and when reset indicates that the node or storage location is available for future use by the processor. The allocator scans selected groups of storage locations in parallel to see if there are any unused storage locations and then places the addresses of those unused storage locations in a queue for use by the processor.

Abstract: In a multiple line adapter organization for a data-comm network, each line adapter providing a receiver-transmitter (USART) and timer means which can interrupt and request service from an associated microprocessor. The microprocessor uses Read operators which can then identify the unit requesting service and identify the type of line operations to be used by that particular line adapter.

Abstract: An assembly of intercoupled integrated circuit die comprises: a substrate having a plurality of holes which extend through the substrate; each hole is of a size that is suitable to receive an integrated circuit die; a plurality of independent subassemblies are also provided; each subassembly includes an integrated circuit die and a heat sink which is attached to the back of the die and extends beyond it; each subassembly is aligned with a respective hole in the substrate such that the die lies in the hole and the heat sink extends beyond the hole and attaches to the substrate; subassemblies are interconnected by printed conductors on the substrate and discrete wires that are bonded from the front of the die to the conductors; and the die and heat sink have similar thermal expansion coefficients, while the substrate has a substantially different thermal expansion coefficient.