Abstract: A nipple type animal watering device is disclosed having an adjustable flowrate, and freeze protection. The flow is adjusted by a screwdriver depression and turning the trigger and without removing or disassembling the nipple. The freeze protection is due to the nipple/trigger relationship and the selection of materials for the nipple and valve body such that a warmer valvebody is easier to maintain.

Abstract: The presently-disclosed invention utilizes sensed pitched rate and sensed vertical acceleration to prevent aberrant pitch rate command outputs as a function of lead compensated sensed acceleration, controlling the vertical acceleration by sensing when a maximum is approached. When the lead compensated acceleration exceeds a first predetermined acceleration factor, the presently-sensed pitch rate replaces the pre-programmed maximum pitch rate factor as the temporary maximum rate, to temporarily prevent additional vertical acceleration due to increasing pitch rate. This apparatus requires no airspeed input and does not interfere with flight performance characteristics during normal flight operations, allowing higher torque servos to be used, and thus improves overall performance.

Abstract: Apparatus and method are disclosed for identifying and measuring random contact interruption events in a circuit interconnection device. A comparator circuit, adapted to be operated at high frequencies, identifies when an interrupt event has occurred. The comparator circuit, as a result of the interruption event, causes a high frequency counter circuit to count clock pulses. The count in the counter circuit is continuously applied to an RAM memory circuit, write-enabled at an addressed memory location. After the interruption event is terminated, the RAM memory circuit is no longer write enabled at the addressed location and the addressed location is changed (incremented) in preparation for the next event. The counter circuit is also reset to zero in preparation for the next interruption event. The number of counts from a clock unit having a known frequency provides the duration of the interruption event. With the use of a clock unit operated at 100 MHz, interrupt events from 10 nanoseconds to 9.

Abstract: A circuit implemented in CMOS technology that controls the rise and fall times of signals applied to conducting paths of a printed circuit board. The circuit consists of an input inverter circuit stage that controls the slope of an output signal from the inverter stage produced in response to an input signal. A second stage is implemented as a source follower and, in response to the inverter stage output signal, provides the output signal applied to the conducting paths of the printed circuit board. A final stage of the circuit compensates for the inability of the source follower stage to utilize, because of the characteristics of the CMOS field effect transistors, the range of voltages provided by the power supplies. The circuit, by controlling the rise and fall time of signal applied to the printed circuit board, reduces the ringing (i.e. the signal undershoot or overshoot) that can accompany application of pulsed signals to the printed circuit board.

Abstract: An improved system and technique is disclosed which enables an aircraft control system to bring an aircraft to hover with no direct measurement of ground speed. The system includes a device for numerically calculating a value for ground speed based on a differentiation of aircraft position as measured from conventional ground reference navigational aids. The computed value of ground speed is compared with values representing heading and true air speed to generate a computed value of wind. The computed value of wind is then resolved into vector components of headwind and crosswind and the headwind component and air speed are summed to provide a signal used to control aircraft speed until zero ground speed is achieved.

Abstract: Disclosed is an alien radio ranging transmitter rejection technique utilizing random PRF to eliminate the possibility of lock-on between two coherent R/T units in close proximity. If one, or both, are utilizing the random PRF technique taught herein, the alien signal is rejected utilizing standard noise suppression techniques. The random PRF is selected utilizing noise or angle data computed from the received return signal and is thereafter utilized to designate which one of a set number of PRF delays is utilized on a substantially random basis.

Abstract: An amplifier signal limiter is disclosed which has the operational capability of tracking slowly varying signal components while precluding errant transient outputs, and has a programmable limit range which is independently controllable for broader or narrower allowable outputs.

Abstract: A digital comparison system and technique enables an easy determination of the digital range within which digital addresses or data may fall or be selected. In one embodiment, the entire memory or addres space is divided into a predetermined number of sections, and each section's location in memory is defined by a predetermined first number of digits of the address. Likewise each address within a section is defined by a second predetermined number of digits of the address. A digital identifier is assigned to each section to define the position of a section with respect to a desired range. Digital identifiers are also assigned to each address within a section to fix the end points within each section. The outputs from memory devices storing the identifiers are coupled through a multiplexer which allows the position of a selected address to be identified as inside, outside, or an end point of a predetermined range.

Abstract: A system and technique is disclosed which enables the production of in-phase and quadrature phase signals useful for deriving phase difference measurements. In an in-phase and quadrature phase difference measurement system, the phase shifter employed must receive an input signal and produce an output signal which is 90.degree. out of phase and equal in amplitude to the input signal over the full frequency range of the input signal. This is accomplished by using a phase locked loop which locks onto the input signal and uses the output of a voltage controlled oscillator located in the loop to derive the sine and cosine of the input signal. The resulting sine and cosine outputs are then 90.degree. out of phase and form in-phase and quadrature phase signals which have equal amplitudes. These two signals maintain lock over the frequency range of the input signal and may be used as inputs in the phase difference measurement system.

Abstract: An automatic digital light source adjustment procedure is disclosed wherein a computer calculates a correction factor for each of a plurality of light sources and adjusts the light sources such that each of the light sources meets an optimum performance criteria. In one embodiment, a multicolor cathode ray tube is converged automatically utilizing the present invention by sensing the profiles of the amplitudes of the individual color light intensities versus the same light source position relative to the sensor mechanism for each of the three primary colors, calculating the correction factor and inputting the correction factor to a digital memory, and then providing for the correction factor to be applied to the analog output of the beam control thereafter. Alternative embodiments enhance focus, purity, light line width, color composition, and other performance factors.

Abstract: A fuel energy analysis system is disclosed utilizing a first hydrostatic sensor, calibrated to specific fuel tank geometries, to monitor fuel quantity; and an additional hydrostatic sensor located at a different geometric height from said first sensor, allowing determination of specific gravity through hydrostatic pressure, and thereafter computation of energy content as a function of mass. This system is particularly suitable for harsh environments such as vehicular applications wherein the quality of fuel input to a tank may frequently vary, and is readily corrected for fluid motion in the tank, by the addition of additional sensors in conjunction with baffles.

Abstract: An improved drive control circuit is disclosed for enabling the multiplexed drive of synchro receivers. A zero crossing detector is coupled to sense the zero crossings of a signal driving the excitation winding of a synchro receiver. A counter coupled to the output of the zero crossing detector responds to one of every n counts to provide a count signal for operating a synchro driver associated with each one of multiple synchro receivers. The count signal causes the synchro driver to provide a signal output to the respective synchro receiver during a period defined by the count signal to reduce average power dissipation and provide effective damping without sacrificing peak current capability.

Abstract: An apparatus is disclosed for displaying arbitrary forms on a raster-scanned cathode ray tube converting the analog X and Y deflection voltages of the raster signal directly into a digital TTL level blanking signal. The circuit designer, utilizing cartesian or polar coordinates, specifies a desired shape and its location utilizing the appropriate formulas. In this manner, a number of raster cut-out circuits are readily coupled to define a desired number of arbitrary shapes on a raster scanned cathode ray tube.

Abstract: A single turn absolute position encoder is disclosed capable of being manufactured in extremely small size while maintaining high resolution. An indented version having a discrete position output signal is disclosed as well as a non-indented continuous position output device having an index for coarse position location as well as apertures for fine position location. This device may be designed for extremely high resolution in a single turn device, or may be geared to further improve resolution.

Abstract: Described herein is a system providing an electronic null-seeking goniometer for use in automatic direction finding equipment. A microprocessor is used to generate sine and cosine information in response to the detected phase of the bearing signal. The microprocessor iteratively locates the transmitter in the null of the cardioid response pattern of the loop and sense antennas, without rotating either the loop and sense antenna set or the goniometer. This eliminates the requirement for moving antenna and goniometer components and is constructed entirely devoid of any rotating machinery. A loop feedback signal functionally related to the detected null angle provides a stable null location method, without audio distortion, at relatively high feedback/signal ratios.

Abstract: A multichannel DME ranging circuit is described which is capable of simultaneous multistation operation. A microprocessor is coupled to control associated peripheral devices and the receiver/transmitter of a DME to produce a multiplexing for receiving frequency data input from up to three DME ground stations. The data received from each of the three DME stations is used to generate timing and interface signals to control the DME receiver/transmitter and associated video processing circuitry. The video processing circuitry is in turn used to provide signals to the ranging circuit to independently determine range, velocity, time-to-station, and the identity of each of the stations providing input to the DME. Each of the three channels is constructed so that it may operate independently of the others to produce rapid acquisition, search, track and identification of each of the particular ground stations to be monitored.

Abstract: There is disclosed a system and technique which enables an aircraft (helicopter or VTOL) to be more easily controlled for maintaining precise position or velocity in a hover condition. The system includes operational logic and decision making circuitry which reduces pilot workload by sensing pilot intent based upon the control stick movement and mode selection of the aircraft. The system will automatically hold a given hover position, automatically hold a given hover velocity (ground speed), or allow the aircraft to be manually maneuvered to a new desired hover position or velocity. The system also enables the aircraft to either hold a new velocity or return to a previous velocity. This is all controlled through the automatic flight control system and by sensing the force or displacement of a pilot's control stick in the aircraft.

Abstract: A multichannel DME ranging circuit is described which is capable of simultaneous multistation operation. A microprocessor is coupled to control associated peripheral devices and the receiver/transmitter of a DME to produce a multiplexing for receiving frequency data input from up to three DME ground stations. The data received from each of the three DME stations is used to generate timing and interface signals to control the DME receiver/transmitter and associated video processing circuitry. The video processing circuitry is in turn used to provide signals to the ranging circuit to independently determine range, velocity, time-to-station, and the identity of each of the stations providing input to the DME. Each of the three channels is operated indpendently to produce a decoded identification of its respective ground station.

Abstract: A system and technique is disclosed which enables an aircraft to naturally respond to pilot inputs during automatic flight control of aircraft attitude or course and to smoothly return to that attitude or course following pilot maneuvers. The aircraft attitude control channels of an aircraft control system are held at a predetermined attitude reference by an automatic flight control system or programmed to follow a particular navigational course by a flight director guidance system. The aircraft control stick is coupled to disconnect the predetermined pitch and roll attitude from flight control following a stick movement of a predetermined distance or the application of a predetermined force to the stick so that the AFCS or flight director guidance system no longer attempts to hold the set attitude or navigational course. The control stick commands an angular rate of change proportional to the magnitude of the pilot's stick displacement or force.

Abstract: An improved vapor phase soldering process and apparatus are disclosed having particular application to electronic circuitry designed for operation at frequencies higher than 1 MHz. A printed circuit board having a defined circuit pattern on both sides is clamped between two parallel clamping fixtures, one having circuit matching characteristics for the specified PC board, and the fixture further having vents allowing vapor phase gas access to the PC board and soldering process waste gasses egress from the soldering area. This process and apparatus allows shortened soldering time, and improves performance characteristics of the PC board by improving the conduction characteristics of the defined circuit pattern.