Abstract: A method of forming a resistor comprises forming a conducting layer on a substrate. An area of the layer is removed such as by etching. A resistor portion is formed in the area. The conducting layer including the resistor portion can be p-Si. The substrate can comprise an insulator such as Al.sub.2 O.sub.3 and a barrier layer can be formed on the substrate to achieve improved radiation hardening.

Abstract: A predictive coding signal communication arrangement includes, at the transmitter, a subtractor for subtracting delayed predicted signals from current input signals to produce difference signals. Predicted signals are generated by adding the difference signals to the delayed predicted signals, and delay of the predicted signals produces the delayed predicted signals. The difference signals are also applied to a coder for Huffman coding, run-length coding, or the like, and then to a rate buffer for reducing data rate variability. In order to prevent overflow of the rate buffer, a control signal is generated which represents the level to which the rate buffer is filled. The control signal is used to control the data rate reduction or decimation of the current input signals. The decimation of the current input signal produces a data rate disparity, which is corrected by a similar decimation of the delayed predicted signal, and an inverse interpolation or data rate increase of the current predicted signal.

Abstract: A system for manipulating articles, such as irregular mailpieces in the U.S. Postal Service mail processing system, receives an agglomeration of parcels into a first subsystem where the parcels are separated and are passed to a second subsystem where each parcel is manipulated until its addressee label is directed upward. The first subsystem includes a plurality of individually rotatable cylindrical rollers which form a support surface for the parcels. The rollers produce translation of a parcel by cooperative motion or separation of parts of a pile of parcels by differential motion. The second subsystem includes a high-friction, flexible conveyor belt which in a first mode supports a parcel and in a second mode forms a downward loop in which a parcel can be rotated and inverted. The parcels in both subsystems are manipulated by a five-axis robotic arm which is responsive to a machine vision system measuring the position and physical characteristics of each parcel.

Abstract: A tuning capacitor arrangement for a microwave circuit including, on a substrate, first and second conductors to be capacitively joined. The tuning capacitor arrangement includes first and second capacitors each having connective tabs terminating on the substrate in the space between the first and second conductors. One or more connective pieces electrically connect one or more tabs to the conductors to determine the total capacitance between the first and second conductors.

Abstract: Digital computer data recorded in a spiral track on the surface of a disk using a laser recording head which moves radially across the disk as it revolves at a constant linear velocity. A system for controlling the disk velocity during the recording process includes a device for counting each convolution of the spiral and means for calculating the number of bits of information which should optimally be recorded in that convolution. A counter keeps track of the number of bits which are actually being recorded in that convolution. The calculated number of bits is compared with the number of bits actually recorded to produce a control signal for regulating the speed at which the disk revolves.

Abstract: A process of forming sub-micrometer metallization structures on a substrate is provided. A layer of a photoresist on the structure is pattern irradiated with a reduced dosage of actinic radiation so that, upon development, recesses are formed therein which extend only partially through the photoresist layer. A first layer of metallization is deposited onto the structure at an oblique angle such that it does not completely coat the photoresist in the recesses. The structure is then flood irradiated with actinic light and developed to form openings to the substrate where the photoresist layer is not covered in the recesses. A second layer of metallization is then deposited at normal incidence. The second metallization breaks off and deposits isolated structures on the substrate through the openings. The photoresist layer and overlying layers of metallization are then removed by conventional lift-off technique.

Abstract: An asynchronous random access system includes stations which in one embodiment transmit information as packets at random times. After a path delay, all stations receive the packets. By comparing the period of activity at the station with the known packet length, all stations know when a collision occurs. According to the system protocol, all station inhibit new transmissions for a predetermined time which includes a retransmission time. Stations whose packets were involved in the collision know that their transmission was unsuccessful, and they can also determine whether their own packets were first or last in the collision, based upon the known path delay. Retransmission of the first and last packets occurs during the retransmission interval and is guaranteed to be successful, because all other stations are inhibited.

Abstract: In systems in which the current digitized level value of a synthesized-signal sample (e.g., a television video signal sample) is determined by summing a transmitted error-signal-sample level value and a delayed previous synthesized-signal-sample level value, the dynamic range of the transmitted error-signal samples are reduced by as much as one-half. This is accomplished by passing the error-signal samples through a first non-linear processor (NLP) before transmission thereof and then passing the summed output through a second NLP. Both NLPs exhibit the same specified transfer function taught by the present invention.

Abstract: A circuit comprises P-channel and N-channel field effect transistors. A conduction electrode, such as a drain, of one of the transistors is coupled to a conduction electrode of the other transistor. Means are provided for ensuring that the currents in the transistors when changing state, and hence the rise and fall times of an output signal of the transistors, are substantially equal. Preferably, the ensuring means comprises the channel length of the P-channel transistor being smaller than that of the N-channel device. Alternately, either the doping level or the width of the P-channel device can be greater than that of the N-channel device.

Abstract: A waveguide power combiner or splitter (divider) includes a common waveguide having an axis skewed relative to the axes of a line array waveguides. A sectoral parabolic reflector is oriented with its focus at a port of the common waveguide with its axis parallel with the axes of the waveguides of the array for reflecting signals from the focal point to create a locus of constant phase at the ports of the waveguide array, whereby signal power originating at the common waveguide is divided equally among the waveguides of the waveguide array. A waveguide power amplifier includes a power splitter as described above, and an amplifier module located in each waveguide of the waveguide array to amplify the power therein to produce amplified signal in an output waveguide array. The amplified signals from the amplifier modules are combined by a second reflector driven by the output waveguide array and reflected to a common output port.

Abstract: A method for making a partially radiation hardened oxide comprises forming a first portion of an oxide layer on a semiconductor body of material at a temperature between about 950.degree. C. and 1400.degree. C., preferably between about 1000.degree. C. and 1200.degree. C. Thereafter a second portion of the oxide layer is formed between the semiconductor body and the first oxide layer at a temperature between about 850.degree. C. and 900.degree. C., preferably at about 875.degree. C.

Abstract: A TEM-mode transmission line such as a microstrip or coplanar line includes a pair of conductors, at least one of which is elongated. A semiconductor junction or junctions are coupled across the conductors. If a single junction is used, the junction may be laterally elongated or distributed. If discrete semiconductor junction devices are used, plural devices may be coupled across the transmission line. The capacitance of the junction(s) controls the phase shift imparted by the transmission lines to AC signals traversing the line. The capacitance of the semiconductor junctions in controlled by light coupled into the junction region. The light is coupled to the junction region by fiber-optic cables or by means of light illuminating the junction.

Abstract: A monolithic chip phase shifter consists of a PIN diode which is laterally elongated and shaped into a microstrip-like transmission line. The transmission line has characteristics determined in part by the capacitances associated with the intrinsic layer of the diode. Alternating-current (AC) signals are coupled through the transmission line. Direct-voltage reverse bias, no bias or direct-current forward bias are applied to select the appropriate value of equivalent shunt capacitance of the transmission line to provide the desired phase shift of the AC signals passing therethrough. A high-impedance coupling device couples the bias to the transmission line to prevent leakage of signal to the bias source.

Abstract: A quasi-parallel IF television receiver derives the AFT voltage from a video carrier in the sound IF channel. Since the signals in the sound IF channel do not pass through the VSB filter, asymmetries in the AFT loop response are avoided. This results in better operation of the AFT control loop.

Abstract: A color subcarrier generator for PAL uses a one-quarter horizontal frequency signal from a sync generator to sample the subcarrier signal. The sampled signal is phase and frequency compared with a 25 Hz (one-half vertical frequency) signal from the same sync generator to control the frequency of the subcarrier signal. Thus the required 25 Hz PAL offset is obtained. The one-quarter horizontal frequency sampling signal can also be used in NTSC and SECAM subcarrier generators.

Abstract: A double conversion television tuner has first and second mixers and uses both the sum and difference frequency signals from the second mixer. The picture component of the difference frequency is separated from the output of the second mixer using a first filter and then demodulated. A second filter passes the sum frequency signal and the second harmonic of the nominally fixed frequency local oscillator signal applied to the second mixer. A third mixer is coupled to the second filter and mixes the converted sum frequency signal with the second harmonic signal. The audio component of the resulting sound signal is demodulated. Because the sum and difference signals at the output of the second mixer are far apart in frequency, the first and second filters can be easily designed so as not to interact.

Abstract: A color beam splitter splits the incoming light into complementary colors such as yellow, magenta, and cyan for improved colorimetry. Stripes are used so that no light is absorbed and therefore a high S/N ratio is achieved. The stripes can be on mirrors or prisms.

Abstract: The resistance between a conductive contact and a region of relatively high conductivity in a body of semiconductor material is lowered by forming the high conductivity region by implanting ions of a desired conductivity type into the semiconductor body through a layer of a material which is electrically innocuous in the semiconductor body and is substantially oxygen free in the layer and at the interface between the layer and the semiconductor body. The layer is applied to the body by first removing any oxide from the surface of the body in an oxygen free ambient and immediately applying the layer to the body while maintaining the oxygen free ambient.

Abstract: An automatic tracking system for a VTR has playback heads having widths smaller than the recorded track widths. At least two tracks are simultaneously reproduced. If mistracking occurs, the amplitude of the reproduced signal from one head decreases, while the amplitude of the signal from the other head remains constant. This is detected and used to generate a bimorph control signal to correct the tracking.

Abstract: A clock pulse regenerator uses a pair of oscillators each comprising a NOR gate and a transmission line feedback element. The oscillators are provided with complementary data pulses and provide an output signal only when the data signal is of a selected logic level. The output signals are combined to form a continuous regenerated clock signal. An FSK encoder using similar oscillators is also disclosed.