Abstract: Disclosed is a coupling arrangement which comprises an enclosed cavity with an aperture in one of its walls. An adjustable probe is positioned within the aperture to allow energy within the cavity to be coupled onto the probe. A microstripline transition is connected at one end to the adjustable probe and at the other end to external circuitry. The arrangement allows variable coupling of energy within the cavity onto the probe without requiring cumbersome procedures for fine adjustment.

Abstract: A scanning CRT graphics video display system is disclosed in which a graphics display controller reads formatted information signals into a refresh memory in a read-modify-wire mode and reads the stored information out of the refresh memory in a display mode. During the display mode the information in the memory is provided on a common data bus for sequential reading into four different shift registers having different bit capacities with the different bit capacities effectively implementing predetermined delays such that the shift registers will properly simultaneously read out the information that was sequentially loaded into the shift registers. A programmable logic sequencer provides address select signals in addition to address signals provided by the graphics display controller so as to address four different memory planes in the refresh memory, and the address select signals are also utilized to sequentially enable the loading of the four shift registers.

Abstract: A fault detection and response system having particular applicability for use with oxygen sensors and closed loop control systems. The system includes a confidence measuring unit as part of a fault control unit (26) that maintains a measure of confidence with respect to the recent operating history of the oxygen sensor. This measure of confidence is increased upon detecting state changes of the oxygen sense signal through use of a state change detector (24), and decreased upon detecting that an integrated form of the oxygen sense signal has attained a predetermined limit as sensed by a limit detector (22). Based upon this measure of confidence, the system can respond to perceived fault conditions in various ways. In general, with a high measure of confidence being present, the system will favor closed loop control even in the presence of a perceived oxygen sensor fault. Similarly, with a low measure of confidence, the system will favor open loop control.

Abstract: A semiconductor device having a plurality of conductive leads extending therefrom is provided for reliably and repeatable positioning and holding a separate electronic device. The conductive leads are disposed apart to provide a predetermined space therebetween. Upstanding sidewall portions of desired dimensions are formed in the conductive leads at a predetermined distance from the central body portion of the semiconductor device. The separate electronic device is inserted in the space between opposite upstanding sidewall portions and is engaged and mechanically held thereby.

Abstract: An incoming signal is received and processed through a discriminator function. A reference signal is generated corresponding to the incoming signal. First and second difference signals, corresponding to the frequency difference between the reference signal and the incoming signal are generated, each having a unique phase. A direction signal is generated from the first and second difference signals to indicate if the incoming signal frequency is greater than or less than the reference signal frequency. Pulses are generated which relate to the difference in frequency between the reference signal and the incoming signal, and a recovery circuit is used for recovering modulation from the generated pulses and the direction signal.

Abstract: In radio frequency applications where energy is coupled between an oscillator device and a reactive load to alter the frequency of the energy at the device, or if coupling of the energy is selectively provided to a plurality of outputs, a PIN diode can be used to electrically switch the coupling of this energy. A significant reduction in current drain can be gotten by using the PIN diode in series with the active device which is amplifying the energy. A current source is used for forward biasing the PIN diode. The same forward bias current is used to bias the active device, saving an additional bias current for the active device. Biasing of the active device, while the PIN diode is reverse biased, is accomplished by an alternate current supply source. Control of each current supply device yields an inverse switching function to selectively couple energy at the active device.

Abstract: 1. Means for searching across a frequency band and instantly stopping at any received frequency, comprising a detector, means for heterodyning said received frequency being connected to said detector, variable oscillator means, means for periodically varying said oscillator over a range of frequencies, means for injecting the frequencies of said oscillator in discrete steps into said heterodyning means, a pulse generator, a pulse-blocking bistable gate means coupling the output of said pulse generator to said oscillator means, pulse-shaping means associated with said detector to instantly form a pulse upon reception of said any received frequency, and means connecting the output of said pulse-shaping means to said gate means to open it in response to pulses from said pulse-shaping means, whereby the frequency variation of said oscillator means is discontinued and it provides a particular frequency in response to the output of said pulse-shaping means.

Abstract: A dual balanced mixer frequency converter is disclosed which provides a low conversion loss by reactively terminating one of the leads on a combiner circuit such that all the image frequency signal power and/or part of the reflected receiver power is returned to the mixer. If this termination appears reactive at the image frequency response looking out from the mixer diode terminals, it will also reduce the noise appearing in the IF output signal.

Abstract: A digital weather radar system having a mode that clears the display of all clutter and lighter precipitation to reveal or positively present only the contoured areas, i.e., the severe "cores" or "hard spots." Data representative of the searched space is stored at least temporarily in a digital memory. In the preferred embodiment, a controllable decoder operates on this data according to the particular decoder state selected, the decoder output is D/A converted, and the resultant analog signal is used to intensity modulate a cathode ray tube (CRT).

Abstract: A redundant channel control system includes one or more voters having a high-pass filter connected between a pair of voter inputs.

Abstract: A postdetection, digital radar signal processor for producing information for a PPI type display on a conventional CRT. Each line of the polar or PPI type display represents a summing of past and present returns received at substantially the same antenna position during past and present antenna scans. SUThis invention relates to electronics and more particularly to digital processors for use with radar systems.Storage tubes, or electrostatic memory tubes, are widely used for radar indicators. The information painted thereon is retained by electric charges and thus such tubes can provide to the operator a continuous map of the system observed space. However, storage tubes are expensive, unstable, and have limited dynamic range. They also require critical adjustments.Previous attempts to replace the storage tube in airborne weather radar applications with a conventional CRT (cathode ray tube) and digital memory have had some success and also some shortcomings.

Abstract: An air erected gyro includes an erection-force producing air stream and gravity-responsive valve means whose gate portion is movable across the air stream so as to vary the erection force magnitude. Also included is a compensator means connected for movement with the gate and for also confronting the air stream so as to at least partially counteract air stream induced horizontal coercive effects on the valve means position.

Abstract: The method of designing a circuit having a substantially constant delay over a given frequency band and having a substantially linear attenuation characteristic or amplitude change characteristic over the same frequency band and the product resulting from such a design approach. One such approach uses a primary tank circuit having a given Q and amplitude response feeding two secondary tank circuits each of which have a higher Q and amplitude response and wherein the resonant points are on either side of the resonant point of the primary tank. By adjusting the Q, amplitude response and resonant frequency of the three tanks, the "delayless" and linear amplitude change characteristics over a given frequency band can be achieved.

Abstract: An amplitude modulation (AM) removal circuit comprising a phaselock loop. A phaselock VOR receiver includes said AM removal circuit.

Abstract: In a helicopter a servo system connected to operate in parallel with the rotor blade pitch controlling linkages and also to receive autopilot generated signals directing maneuvers. The system limits the autopilot control over the blade pitch or position in the short term and permits full control over the long term.

Abstract: A communication system is illustrated wherein the communication links include automatically reversible amplifiers with the termination means of two links closing a loop. Upon failure of detection of a carrier signal in one of the links at the terminating end due to a break in that link, switches are automatically actuated to connect the momentarily unconnected portion of the broken link to the link that is still intact such that communication is restored in a new link configuration thereby accomplishing "fail-safe" operation without undue redundancy.

Abstract: Apparatus for testing the operability of a signal translation means which passes signal information containing a definable and repeatable characteristic such as a synchronization signal through the use of a spare similar device and a demodulating device which provides outputs upon detecting the signal passed by each signal translating device. As illustrated, regular and spare transmit multiplexing devices are used and logic information obtained from a spare receiver is used to indicate a failed condition.

Abstract: Method and apparatus for limiting the authority of a position servo system over an aircraft control surface. The amplitude of the energizing signal delivered to the actuator portion of the servo system is limited in accordance with a non-constant function of time.

Abstract: An input tracking threshold detector includes a first circuit receiving input signal, a feedback signal, and a predetermined gating signal. The first circuit outputs a binary signal which during gating signal enablement intervals is indicative of the relative amplitudes of the input and feedback signals. The feedback signal is developed from the first circuit output by a second circuit whose output signal amplitude is indicative of the duty cycle of its input.

Abstract: Temperature sensing apparatus utilizing a single temperature sensing diode which is supplied with a constant level of current. The voltage across the diode having the constant current therethrough is compared with a constant voltage reference in a summing means and the deviation of the sensing diode with respect to the constant voltage reference is utilized as an indication of temperature.