Abstract: An improved circuit is provided for extending the write-recovery time of a high speed memory into the next memory access cycle. In the preferred embodiment, the address buffer circuits turn off at a suitable high rate for read but are controlled to turn off more slowly for a write and to thereby extend the write select signal. In a specific address buffer circuit, FETs are supplied a reduced drain-source current during write and thereby are made to switch at a suitably slower speed.

Abstract: Apparatus for measuring the heat produced by a circuit module that is mounted on a circuit board has a tubular housing of a thermally resistive material such as plastic that is adapted to be placed over the module so that substantially all of the heat from the module flows along the axis of the housing, A thermal resistance is located between two metal partitions in the housing. The temperature drop through the resistance is calculated from the temperatures of the two partitions and the heat is calculated from the temperature drop and the value thermal resistance, The apparatus is adapted to make good thermal contact with the top of the module and cooling apparatus is provided for cooling the upper one of the two partitions. The upper partition is adjustable to vary the length of the thermal resistance in order to keep the temperature drop around 2.degree. C. for modules of different power ratings.

Abstract: A circuit for protecting a CMOS chip against damage from electrostatic discharges (ESD) has four SCRs connected between the line to be protected and the two power supply terminals, V.sub.DD and V.sub.SS. The SCRs are poled to conduct ESD current of either polarity to each power supply terminal. The bipolar transistors for the SCRs and the associated components are arranged in the chip in an advantageous way that reduces the input/output parasitic capacitance and improves the protection capability of this proposed circuit with a low ESD trigger-on voltage.

Abstract: A video recording disk is adapted to be rotated at a uniform angular velocity and to have bit positions of substantially equal length along a track, and the longer outer tracks are given more storage positions than the shorter inner tracks. Variable numbers of frames are located on each track revolution, depending on the data capacity of the track. Frames are divided into data units that correspond to a few horizontal lines, and frames on the same track are interlaced so that the data units of each frame are distributed evenly around the track revolution. The associated record player has simplified data storage requirements, particularly for freeze frame display of the television picture and for playing disks that hold video information in a data compression format.

Abstract: A video recording disk that is optically readable has data represented in a form that permits data track revolutions to be spaced close together without an intervening guardband or with only a narrow guardband. The track revolutions are in two sets that form a parallel spiral or alternating concentric circles so that a track revolution of one set is separated from other track revolutions of the same set by intervening track revolutions of the other set. Binary data is represented on the tracks by deformations or the absence of deformations, and the record is read as destructive interference in a light beam produced at the location of a deformation. Deformations of the first set of tracks have a depth that is appropriate to be read with a wavelength designated lambda 1, and deformations of the second set have a depth to be read by light of a wavelength lambda 2.

Abstract: An improved sample holder for a spectrophotometer includes a stationary base that forms a cylindrical cavity and supports a fiber optic head assembly over the cavity for analyzing the color of a sample that is positioned adjacent the base and under the cavity. The fiber optic head assembly covers the top of the cavity and the area of the sample that is to be color analyzed is not visible to an operator of the spectrophotometer. A shutter mechanism is arranged to be moved in an opening in the base between a closed position in which the shutter forms part of the cylindrical wall of the aperture and an open position in which the opening in the base permits an operator to view the sample. A prism is provided to raise the viewing position of the operator to the normal position of the operator.

Abstract: A method of optically printing conductive characters using charge transfer compounds is provided. The method is characterized by depositing an organic .pi. electron donor compound dissolved in a halogenated hydrocarbon (halocarbon) on a suitable substrate and selectively exposing the so coated substrate to actinic radiation to obtain a permanent, highly conductive, image.

Abstract: An improved tablet system is disclosed of the type having an array of X dimension wires and Y dimension wires that are capacitively coupled to a pen that a user holds to the tablet to produce a position signal. The X and Y wires are individually coupled to drivers so that the wires on one side of the pen position can be activated and the wires on the other side can be not activated for a pen position sensing operation. To reduce the number of drivers required for a large tablet, the wires are arranged in groups with an individual driver capacitively coupled to a correspondingly positioned wire in each group. A new packaging arrangement is provided and a new system is provided for addressing the drivers to produce the selected activation pattern.

Abstract: An improved tablet system is disclosed of the type having an array of X and Y dimension wires that are capacitively coupled to a pen that a user holds to the tablet to produce a position signal. Drivers are provided for individual wires to produce a selected activation pattern for the wires. The drivers are operated from a shift register and associated components that are mounted on the tablet and are connected to an associated processor through only a small number of conductors.

Abstract: A modular control system is provided for a gas panel of the type having an array of row wires and column wires that form light emitting cells at their crossover points. A row counter and a column counter provide selection signals for entering characters sequentially on the panel. The counters provide borrow and carry signals to components that control the display. Thus, the control operates without regard to the actual size of the display and provides a modular construction for displays of various sizes.

Abstract: An improved write circuit for a gas panel produces a sequence of alternating polarity write pulses that are superimposed on a sequence of half cycle pulses of the sustain waveform. Thus the accumulation of charges on the walls of a light-emmitting cell that is required for a write operation is produced by a sequence of write pulses, and each write pulse is lower in amplitude than is required for a single write pulse. The write pulses are progressively shifted ahead in phase to further improve the operation.