Abstract: The electroplating of various metals such as zinc, copper, cadmium, chromium, nickel cobalt, gold, silver, palladium, platinum, ruthenium and alloys of such metals takes place from electrolytes comprising heterocyclic additives such as lactones, lactams, cyclic sulfate esters, cyclic imides and cyclic oxazolinones. Specific examples of such additives are phenolphthalein, phthalide, phenolsulfone-phthalein, naphtholphthalein, 2-benzoxazdinone and phthalimide. These additives may be used in conjunction with various polyethers to permit high plating rates, constant plating thicknesses over wide areas and smooth coatings.

Abstract: A high voltage solid-state switch uses a dielectrically isolated lightly doped p- type semiconductor body with a heavily doped p+ type anode region, a heavily doped n+ type gate region, a moderately doped p type shield region, and a heavily doped n+ type cathode region. The shield region surrounds the cathode region. Separate electrodes contact the anode, gate, shield, and cathode regions. The gate and cathode regions also act as the collector-emitter output circuitry of an n-p-n transistor with the shield region acting as the base. With the shield (base) region forward-biased with respect to the cathode or gate regions, the n-p-n transistor is biased on and the collector and emitter are rapidly pulled close to each other in potential. With proper operating potentials applied to the anode and cathode regions, the switch rapidly assumes an "ON" state when the potential of the shield (base) region is set to a level which biases the n-p-n transistor ON.

Abstract: The present invention relates to a technique for increasing the rain margin at ground stations of a satellite communication system. In the present technique, spare TDMA time slots in each frame sequence are shared among all ground stations as required by stations experiencing a fade condition which exceed a predetermined power margin. Additional up-link power margin at a faded transmitter can be achieved by either increasing power transmission of a normal burst or by the use of spare time slots plus encoding and preamble field extension techniques for burst extension. Additional down-link power margin to a faded receiver is accomplished by either increased transmitter power transmission or by the use of burst extension and coding and field extension techniques. Apparatus for implementing framing, carrier and clock recovery and start of message detection using extended fields and coding techniques for other data at a transmitter and receiver and disclosed to overcome fade conditions.

Abstract: A detection circuit for detecting a mismatch between the output signals of duplicated logic units (10a, 10b). The output terminals of one of the duplicated logic units are correspondingly connected to the output terminals of the other duplicated logic unit, while the power supply leads of the duplicated logic units (10a, 10b) are connected to a positive voltage source (32) through a current imbalance detector. Any mismatch between the output signals of the duplicated logic units (10a, 10b) will result in the detection of a large imbalance of current being supplied to the duplicated logic units (10a, 10b). Upon detection, the detector will generate an error signal.

Abstract: Display devices are described which contain organic quinones or diones as active material. These devices exhibit high optical contrast, pleasing and striking colors and unusually low power consumption. Particularly advantageous is the fact that these display devices may exhibit non-linear behavior (sharp thresholds) which permit multiplexing. This is highly advantageous in display device applications.

Abstract: A computer input/output arrangement is disclosed which utilizes a rotate memory instruction of a computer instruction set for performing a bit by bit read/write data transfer between the computer memory and a connected peripheral device. The arrangement enables the rotate memory instruction to perform read and write steps simultaneously from memory and the peripheral device. During the read step data is simultaneously read from the memory location and the peripheral device into associated locations in a computer register. The register data is rotated such that the received data in the peripheral device bit location is rotated into the memory bit locations of the register while simultaneously rotating a memory data bit into the peripheral device bit location. The write step writes register data from the peripheral device bit location to the peripheral device while simultaneously writing the data from the memory bit locations into the memory.

Abstract: A process is described for producing devices and articles with gold films made by gold evaporation in which certain fluoride compounds are used to insure good adhesion of the gold film to the substrate. The process is particularly applicable to the production of gold films on non-metallic surfaces such as ceramic and glass surfaces. This procedure not only insures better adhesion of the gold film to the surface, but also permits greater processing variations without adversely affecting film adhesion.

Abstract: In a digital transmission system, disparity is defined as the difference between the number of binary digits at each code state. The generation of a block of binary digits having zero disparity possesses many advantages. The present invention discloses coding apparatus (100, 300) for converting a block of binary digits having random disparity into a zero disparity block, and vice versa. The coder accomplishes this translation by determining (103) the disparity of the random disparity block and then selecting (103, 104, 106, 107, 110, 111) a bit position which divides the block into two digit segments each having half this disparity. Inversion (115) of either digit segment generates a zero disparity block. For decoding, data representing the bit position selected is transmitted along with the zero disparity block. The binary digits previously inverted by the coder are then reinverted. This coding/decoding technique is adaptable to any block size having an even number of binary digits.

Abstract: An rf sputter etch or reactive sputter etch apparatus which can be used for etching substrates at oblique angles utilizes a cathode formed from a metal grid and an equipotential enclosure. The substrate is supported in the enclosure either parallel to or at an oblique angle to the surface of the grid.

Abstract: A method and apparatus are shown for precision distance or displacement measurement using a light source and a detector. A light emitting diode or laser are typical sources, and a photodiode or phototransistor are typical detectors. Light from the source is directed towards the detector directly, or reflected onto the detector by a reflective surface. By tilting the axis of the light source and detector, high sensitivity is possible. The effect of the tilted axes may be obtained by the use of two reflective surfaces. Typical resolution is on the order of 5 microinches over a range of 50,000 microinches (i.e., one part in 10.sup.4) using simple associated electronics, with higher resolution possible.

Abstract: Buffer circuitry, which uses enhancement and depletion mode field effect transistors, has relatively high speed operation, low power dissipation, and requires a relatively modest amount of silicon area for implementation.

Abstract: A current controlled switching type voltage regulator achieves voltage regulation by controlling an average current flow through the switching device. This current is sensed and transformed into a signal frequency. The signal frequency is counted to determine its average value and this count is compared to a variable current reference count which is continuously adjusted in response to an output voltage monitor which includes circuitry to generate an error count responsive to the deviation of the voltage output from a desired regulated value. In order to counteract instability problems inherent in current controlled switching type voltage regulators the transducer converting current into a signal frequency has a threshold characteristic to insure a definite fixed signal frequency at very low currents.

Abstract: A simple and inexpensive direct current voltage level detector is shown which has a significant immunity against interfering alternating current signal components. The output of a standard analog threshold detector is successively sampled by clock pulses having twice the repetition rate of the frequency of the expected interfering alternating current components. By requiring two successive samples to be above the threshold of detection, immunity is provided against false detection due to temporarily exceeding the threshold level due solely to the positive excursion of the interfering alternating current components. Simple clock-driven flip-flops are used for the sampling and a simple logical AND gate is used to detect the successive samples.

Abstract: A method of fabricating an optical fiber having an asymmetric refractive index profile that varies periodically along the length of the fiber is described. The prescribed variations are obtained by means of a fabrication process that includes periodically varying the source of at least one of the fiber materials in a direction transverse to the fiber-drawing direction. This transverse periodicity is translated into the desired longitudinal periodicity along the fiber by the fiber-drawing process.

Abstract: An arrangement for controlling switch connections (115) between a plurality of accessing circuits (113a through 113n) and a plurality of peripheral circuits (116) prevents simultaneous connections by more than one accessing circuit to any one peripheral circuit. Address signals which identify requested connections are decoded to generate connection request signals. A resistor network (501A through 501N and 506A through 506N) responsive to the connection request signals generates voltage level signals representative of the number of accessing circuits requesting connection to each peripheral circuit. The voltage level signals are compared to a threshold signal to generate a connection enable signal if only one accessing signal is requesting connection to a given peripheral circuit and to generate a busy signal if more than one accessing circuit is requesting connection to a given peripheral circuit. Switch connections are completed only after receiving a connection enable signal.

Abstract: A new type of electrical contact is described which has reduced erosion and sticking failures and has reduced material costs. The electrical contact is particularly suitable for sealed electrical contacts such as in sealed remreed contacts.

Abstract: A method of observing the core region of optical fibers and fiber preforms is disclosed comprising the step of inducing fluorescence in at least one of the index-modifying dopants present in the core being observed by illuminating said fiber/preform with radiation at the peak absorption wavelength for said dopant, and observing the region between the fluorescing edges of said fiber/preform. The core diameter can be determined by measuring the distance between said edges. This technique can be utilized to control the fiber pulling rate during fabrication.

Abstract: An optically toggled bilateral field effect transistor switch having a low leakage current is described. A high impedance path and, therefore, a low leakage current, is provided by a photovoltaically controlled field effect transistor.

Abstract: An electrical protector device (10) for grounding excessive voltage and excessive current to safeguard telecommunications circuits includes a heat coil assembly (100) for sensing and directing excessive current to ground, and a spark gap arrester (200), axially aligned with the heat coil assembly (100), for sensing and controlling excessive voltage. Whenever an overcurrent condition is encountered, heat coil mechanism (110) is displaced to provide metallic contact of the incoming line to a ground structure (300). In addition, the device is adapted to provide protected testing of both incoming pairs and office equipment. Two test points (123) formed as part of the heat coil assembly (100) are in contact with the individual wires of the incoming line. These two test points are accessible through apertures (402) in the protector housing (400).

Abstract: Computer graphics material after raster scanning and digitizing is examined for linear narrow width areas of like light value, typically black or white. Runs of like value on successive scan lines are compared for contiguity and, when found, are compactly coded by coordinates of first and last scan lines defining each area and thickness. Data compaction ratios up to 36 to 1, as compared to the amount of data required to store data for every picture element, can be achieved in real time.