Abstract: An apparatus for applying convergence corrections to correct positional and misconvergence errors in a CRT employing a self-converging deflection yoke for magnetic deflection of an inline color gun assembly. Convergence correction coil windings are coupled to the deflection windings with the inductances and resistances of the convergence windings selected to match the time constants of the associated deflection windings. The applied deflection current signals are thereby apportioned between the deflection and convergence coils to modify the beam deflection and provide a beam deflecting flux proportional to the commanded deflection signals and a beam deflection center that is independent of the pattern written on the screen. The resulting currents in the deflection coils and convergence coils are a substantial replica of the commanded deflection current signal waveforms.

Abstract: An improved method for the automatic acceleration of an aircraft to a preselected speed is described. At any point in the climb portion of flight, a capture of a computed altitude that is increased at a specified rate is performed to provide optimal acceleration.

Abstract: Apparatus for providing precise convergence measurements of electron beams in a CRT display by sensing the displacement of brightness peaks as an array of phosphorescent regions are sequentially illuminated by energy from the electron beams deflected by the deflection apparatus of the display system and an independent external time varying magnetic field applied by enclosing the CRT housing within a pair of external coils. Convergence is calculated by calibrating the recorded brightness peaks as a function of beam displacement. The system is adaptable to measuring both vertical and horizontal components of convergence as well as linewidth. The apparatus operates independently of and does not require interruption of dynamic functions which operate in synchronism with the deflection circuits, such as dynamic convergence correction.

Abstract: A magnetic actuator for providing a single-axis, noncontacting force capability with unconstrained cross-axis mobility utilizes flux feedback force linearization. Electromagnets cooperating with an armature suspended therebetween are energized by a bias flux and a signal derived from flux densities sensed in the air gaps. The bias flux density may be optimized to minimize the peak power required by the actuator. The flux density signals are applied in a closed force loop to provide a net force directly proportional to the commanded flux.

Abstract: A cathode ray tube provides a raster can symbol display superimposed on a stroke vector display, with selected regions of the stroke vector display preferentially masked in response to priority instructions. Stroke vector priority data is loaded into a full-field bit-mapped memory by a raster symbol generator and used to provide a stroke vector masking signal in synchronism with the picture elements of the raster scan. The system provides efficient generation of dynamic stroke priority areas by utilizing the repetitive nature of the raster scan to load the stroke priority full-field bit-mapped memory without requiring corresponding processor intervention.

Abstract: A color cathode ray tube has raster scan color zones defined by X and Y positional signals derived from a stroke vector generator and stored in a digital memory. Raster scan and stroke vector displays are alternately presented in a hybrid display. The display face of the tube is scanned by a plurality of raster lines and a color transition point is defined by the intersection of a stroke vector with a raster line. The X and Y addresses of the intersection points define the raster line, pixel element, and color at the transition point. The system is arranged so that the X and Y addresses are provided by the stroke vector generator in synchronous relation with the color transition points, and read into memory during the stroke vector refresh period. During the raster scan refresh period, the memory contents are recalled in synchronism with the raster scan, passed through a digital to analog converter, and then applied to the display tube to provide filled-in color zones superposed on the stroke vector display.

Abstract: An apparatus for providing a signal representative of armature displacement in a magnetic bearing assembly for a magnetic suspension system, of the type having a force sensor applied in a closed loop to provide a linear response with respect to an input force command signal. Signals representative of currents applied to the magnetizing coils and of the sensed force are used to derive the armature displacement signal. The signal so derived is applied to modulate the magnetic flux and obviates the need for proximity devices for sensing armature displacement. A circuit for generating the armature displacement signal is provided.

Abstract: A helicopter flight control system employs coupled torque limiters in the rotor cyclic pitch axis and collective pitch axis for airspeed and vertical path control, respectively. When the collective torque limit is reached, the cyclic pitch axis is automatically transferred to favor vertical path control. A synchronizer circuit is provided for assuring smooth acceleration transition to reduce accrued airspeed errors when the engine torque limit is no longer commanded.

Abstract: An apparatus for sensing and measuring changes in inclination and providing a digital readout. By sensing pulse width changes rather than amplitude, the apparatus provides improved immunity to instability and environmental changes. A variable frequency scale factor oscillator allows choice of readout units. Any preset angle may be selected as a zero reference. The capability is provided to hold any reading displayed for any desired period of time. An overrange indicator is actuated when the linear range of the sensor has been exceeded. Digital output signals derived from the sensor are applied to gate an angle generator which is responsive to correction factor signals to adjust the digital count in accordance with stored offset data. The digital signal count is incremented or decremented in accordance with a signal representing the sign of inclination, derived from the sensor pulse widths and applied to gate the angle generator accordingly.

Abstract: A magnetic head slider for supporting a flying head on a magnetic disk has a plurality of rails extended longitudinally between the slider and the disk which provide the air bearing surface and define a channel parallel to the motion of the data track. A flexible beam is affixed to the leading edge of the channel providing a cantilever structure. A magnetic head is mounted on the free end of the cantilever. A pair of oppositely polarized piezoelectric crystals are mounted on the cantilever assembly. When energized by an electrical driving source, the cantilever beam is flexed upwards or downwards thereby changing the distance of the magnetic head from the disk. A capacitive proximity sensor is coupled to the magnetic head for sensing the height of the head above the data track. The output of the sensor is fed to the driving source and energizes the piezoelectric crystals in the polarity desired for the corresponding deflection of the cantilever structure.

Abstract: A fluid sphere gyroscope is used as the north-seeking sensing element in a gyrocompass. A sensor responsive to angular deviation of the gyroscope from the horizontal provides a tilt signal which is used to energize heating elements located along the independent spin axis of a rotating fluid mass. Application of a thermal gradient along the spin axis of the fluid mass causes a controlled precession of the gyroscope, thereby compensating for bias and acceleration sensitive drift errors and precessing the gyroscope about a vertical axis in a controlled manner. Rotary transformers permit inductive coupling of the heating elements to the tilt signal and to a power source with minimal disturbing torques.

Abstract: An aircraft speed control system for use with an automatic throttle position control system and automatic flight control system permits capturing and maintaining a commanded airspeed during the capturing of a desired altitude from either climbing or descending flight. The system manipulates the throttles at a variable rate dependent on the difference between the actual thrust of the aircraft and the desired cruising thrust at the selected airspeed and inversely proportional to the actual altitude rate. A signal derived from thrust error and altitude rate signals is utilized to generate a limiter control signal which is combined with an engine pressure ratio signal to generate a drive signal for urging the aircraft to capture precisely the commanded airspeed.

Abstract: A hermetically sealed quasi-planar integrated circuit suitable for millimeter-wave transmission. The circuit is enclosed within a module having a metal frame soldered to a quartz window. Active elements, such as beam-lead diodes, are mounted on a conductive layer housed within the frame. The assembly is evacuated and may be filled with an inert gas to avoid condensation in humid operating conditions. The invention is particularly adaptable to use in a cross-bar signal mixer at frequencies up to 140 GHz. The structure is adaptable to cooling to reduce circuit losses and improve performance and operating efficiency. Resonant cavities are provided to permit tuning the mixer to fixed frequencies.

Abstract: An optical waveguide apparatus provides for single-mode and multimode switching or modulation of light wave energy with reduced bias voltages. Optical channels are formed in a crystal substrate by depositing film stripes thereon to cause stress-induced changes in the relative refractive index. Coupling or switching of light waves between the channels is provided by applying a bias which is of reversed polarity at adjacent film stripes, thereby augmenting or diminishing the stress in individual channels. By allowing operation with close spacing of the electrodes and using the enhancement in refractive index change of the stressed substrate in combination with the applied bias, the required control voltage is substantially reduced.

Abstract: Superconductive integrated logic gate circuits of the magnetically controlled type incorporating Josephson tunnel junctions utilize a superconductive layer that forms a base electrode for Josephson junction devices on the integrated circuit, a ground plane, and magnetic control lines. A layer of super-conductive material superposed on a barrier layer provides inductive loops connected to junction counterelectrodes and coupled to the magnetic control lines. By patterning the control lines in the same plane as the ground plane-base electrode layer, two layers, an insulating layer and a super-conductive layer, can be eliminated from the prior art structure of a 1:2:1 magnetically controlled logic gate interferometer. A preferred embodiment utilizing an all refractory superconductor-barrier-superconductor trilayer patterned by local anodization is also described. Processes for manufacturing the embodiments of the invention are disclosed.

Abstract: An angular measuring system consisting of one or more sensors that transmit angular measurements to a central control unit where numerical readout of any selected sensor is provided. A threshold can be preset at individual sensors or the control unit for an allowable angular deviation, beyond which a warning device is actuated. The circuitry permits locating the sensors remotely from the console and provides precision and stability of operation. Low power consumption permits extended operating periods with internal batteries. False alarms are minimized by incorporating a hysteresis loop in the threshold detection circuitry.

Abstract: A thin film passive integrated optical waveguide is formed in a lithium tantalate substrate by proton exchange in a benzoic acid bath. Annealing the substrate provides increased waveguide depth and stabilizes the refractive index. Optical components are formed by proton exchange of the masked substrate after formation of a planar waveguide.

Abstract: An apparatus for color and brightness correction for a multi-gun color CRT display, providing compensation for variation in phosphor efficiency with cathode energization and for color tracking between guns. The brightness correction circuit is required to respond only to essentially DC changes, while a color selection circuit responds at a video rate. In a preferred digital embodiment, brightness and color tracking correction factors are stored in memory dedicated to a particular CRT, and addressed in response to input from a reference brightness level selected by an operator. A color selection decoder having stored in a second memory relative brightness characteristics of each color phosphor as a function of the hue commanded converts an input binary command to an analog output, which is combined with the brightness and color tracking correction factor to determine the resulting cathode energization for each color gun.

Abstract: In superconductive integrated circuit a semiconductor substrate is used in combination with normal resistors formed by degenerate doping of the substrate in selected regions. Doping is preferably performed by planar diffusion or ion implantation. Application of the invention to fabrication of a Josephson Atto-Weber gate by forming a normal resistor intermediate the junctions is also disclosed.

Abstract: A quaternary saturated digital magnetic recording system for enhancing information entropy provides an effective bit density increase of 100% or more over the MFM code. In the simplest implementation, groups of two input binary bits are mapped into one data cell, preferably into four combinations of long or short breaks and positive or negative polarity, with the break optionally centralized within the data cell for self-clocking. A system for reproducing the recorded information provides a peak detector, responsive to the recorded signal, coupled to pulse polarity and break width detector circuitry, with an internally synchronized clock, for remapping the recorded data into binary format.