Abstract: A method is disclosed wherein information can be conveyed serially over a signal path in a rate-independent fashion. Three or more signal states are employed for conveying information. The disclosed method consists of attaching meanings to changes of signalling state rather than the length of time that a state is maintained. It is only required that the data source and data sink establish meanings for each change of state and that each transmitted state be maintained long enough for the receiver to detect it.

Abstract: A closed loop head positioning servo system is disclosed for use in a disk drive employing a disk pack having a dedicated servo surface and a number of data surfaces carrying both data and servo information. A track counting coarse positioning system is used to move the heads in a ganged assembly to the vicinity of a desired cylinder. A fine positioning system includes one error circuit for generating an error signal representing the deviation of a servo head from a desired cylinder on the dedicated servo surface. Another error circuit generates a second error signal representing the offset of a selected data head from a selected data track in the same cylinder. Analog circuits combine the error signals to produce an output signal which, when applied to an actuator, centers the selected data head on the selected track.

Abstract: A method for obtaining adhesion of multilayer thin films through the use of a conventional sputtering system. The adhesion between the multilayer thin films is obtained by forming a graded interface between a deposit material and a substrate using an adhesion layer material. The graded interface is formed by sputtering a uniform layer of the adhesion layer material on the surface of the deposit material. The deposit material is coated on a sputtering cathode. The subsequent sputtering from this cathode results in the graded interface between the deposit material and substrate due to the radially non-uniform rate of removal of the adhesion layer material and deposit material from the cathode's surface.

Abstract: In an associative memory, each cell 20 (FIG. 2) includes a recirculatory shift register 30 in which information is stored, a comparator 31 for comparing the stored information with a key fed on line 22, a gate 32 for passing the results of the comparison only in a key field defined by key field signals on line 23, and a flip-flop 33 which is set to 1 if the comparison fails. Flip-flop 33 controls reading from the cell. A flip-flop 37 is used to record whether the cell is full or empty, and a compare chain 40a, 40b passing through all cells in sequence is energized onwards from the first cell in which comparison is successful.A further development permits sequential retrieval and searching for the next key above a desired key if the desired key itself is not in the memory.

Abstract: An apparatus and method for electrographically printing on a dielectric paper and transferring a toned image from the dielectric paper to plain paper. The dielectric paper receives an electrically charged latent image from an electrode device. The latent image is developed by applying a liquid or dry toner. The toned image on the dielectric paper is transferred onto the plain paper by conveying the dielectric paper and the plain paper together through a pair of conductive rollers. The dielectric paper is dried, fusing the residual image on its surface. The dielectric paper is then reused. The plain paper with the transfer image is dried, cut, and stacked.

Abstract: A system is provided for positioning a transducer over a magnetic media by the sensing of previously recorded information. The previously recorded information is in the form of a plurality of tracks containing position information. A servo transducer traverses a path over the tracks of position information and produces a signal in response to sensing the position information. A position detection circuit analyzes the signal thus produced and defines two separate data tracks for each and every individual track of position information thus traversed.

Abstract: An electrographic printer is provided with a multiple row electrode structure wherein the electrodes in each row are mutually spaced one from the other and the electrodes of successive rows are staggered with respect to one another. The electrodes are each characterized by being of a smaller dimension in the direction of movement of the print medium than in the transverse direction, and an electrode drive circuit operates to maintain the electrodes activated when the print medium is moved across it to produce a latent image on the print medium.