Abstract: A test circuit for determining the current produced by a current source device with a predetermined, non-zero voltage at the output of the device. The circuit includes a current to voltage converter circuit for converting the current produced by the current source device, typically a digital-to-analog converter (DAC), into a corresponding voltage. A control voltage source is coupled to the output of the current source device and to the current to voltage converter circuit through a coupling circuit. The coupling circuit couples a predetermined portion of the control voltage to the output of the current source device and to the current to voltage converter circuit with the voltage produced by the current to voltage converter being proportional to the current produced by the current source device and independent of the control voltage.With such an arrangement, the compliance voltage range of a DAC may be accurately measured.

Abstract: A photon absorber minimizes the mixing of unwanted reflected electromagnetic waves with the main clockwise and counter-clockwise propagating electromagnetic waves of a ring laser gyroscope. A round hole in the middle of the absorber allows the main waves to pass and an angulated front surface deflects reflected waves away from the main waves. Most of the reflected waves which impinge on the photon absorber are absorbed. A photon absorber is fabricated from light absorbing filter glass with anti-reflection coatings or from beryllium-copper with an absorptive coating.

Abstract: A connector holder assembly for use with a wiring harness wiring has a frame adapted to hold a connector contained with the frame by a snap-on cover. A pair of jackscrews secures the frame to a mating connector. The frame is cast with two arms at each end of a back plate. The arms have inboard slots for receiving jackscrews. The jackscrews are retained within the slots by a connector which has detents at its ends which engage the jackscrews when the connector has been positioned between the jackscrews. A stiff spring-like metallic retainer cover for the connector which is snap fastened to the arms of the frame retains the connector between the frame arms and against the backplate of the frame against the force produced on the connector by the wiring harness attached thereto.

Abstract: A memory system adapted to store samples of a finite portion of a periodic signal and produce an output signal having the same frequency as the periodic signal for a relatively longer time duration. The system includes a network for comparing the initial and terminal portions of the finite portion of the stored signal to determine the relative phase shift therebetween. Portions of the samples of the stored periodic signal and of the phase delayed replicas which extend from the first sample to the next to the last sample thereof are sequentially coupled to an output selectively in accordance with the determined relative phase shift to produce the output signal.

Abstract: A digital-to-analog conversion circuitry is provided wherein a switching network is adapted to couple, or decouple, a selected one, or ones, of a plurality of identical current sources to, or from, an output bus selectively in accordance with the digital word being converted to produce an output current through an output bus having a level related to such digital word.

Abstract: A display system line generator network having an error correction feedback loop which achieves high positional accuracy for both plan position indicators PPI and synthetic character and line data. Digital reference position and relative beam motion data are fed into separate D/A converters. The staircase effect at the output of the D/A that processes the relative beam motion data is eliminated in a constant current integrator. The output of the integrator is combined with the reference position signal in a summing amplifier and the summed signal is fed to a deflection amplifier. A feedback circuit picks off the inputs to the summing amplifier and uses their comparison to synchronize time with beam position by compensating for errors due to component drift and aging.

Abstract: An antenna system is provided for producing a plurality of differently directed beams of electromagnetic energy, each one of such beams being associated with a corresponding one of a plurality of beam ports, each one of such beams being produced from a common array of antenna elements. The antenna system includes a radar frequency energy lens assembly having a plurality of array ports coupled to the plurality of antenna elements. The lens assembly includes a radio frequency lens having a plurality of lens ports disposed about peripheral portions thereof. Each one of a first portion of such plurality of lens ports is coupled to a corresponding one of the antenna elements through a corresponding one of the array ports and each one of a second, opposing portion of the plurality of lens ports being coupled to a corresponding one of the beam ports. Each one of the lens ports in one of the portions thereof includes a pair of tapered feeds.

Abstract: A fluid mixer arrangement such as for mixing fluid concentrates with water to produce a mixture available on a demand basis. One embodiment includes two such mixing arrangements particularly suited to semiautomatically provide separate fixer and developer fluid mixtures for film development. In each mixer arrangement, bottles of liquid chemicals are positioned in inverted fashion above a tank with hydraulically operated piercing knives located to pierce the caps of the bottles to replenish the chemical mixture in the tank. When the mixture of fluid in the tank reaches a certain minimum level, a secondary float permits a valve to open, coupling pressurized tap water to cylinders to activate the piercing knives and also to permit water flow into the tank. A primary float closes the valve when the fluid mixture in the tank reaches its desired high level.

Abstract: In a radar or sonar system wherein the detection of a target is to be accomplished with a constant false alarm rate (CFAR), a circuit is provided for adjusting the input to a comparator which compares the received echo signals against the value of a threshold in order to detect targets of interest. The mean value of the background noise is subtracted from the signal, and the resulting difference is divided by the square root of the variance of background noise. The use of the variance compensates for sweep-to-sweep correlation and non-stationarity (in the statistical sense) as is found in clutter so that the clutter, upon the customary sweep-to-sweep integration of the signal, does not tend to introduce a false echo.

Abstract: A conveyorized microwave oven having two leakage suppression tunnels in series wherein the first tunnel includes a microwave choke and a second tunnel has a ferromagnetic layer covered with a smooth microwave transparent sheet. The choke tunnel presents a high impedance to microwave energy at the operating or fundamental frequency and the second tunnel attenuates spurious out-of-band radiation which propagates through the first tunnel and is typically concentrated at the harmonics. The ferromagnetic layer absorbs the broad-banded microwave energy and the smooth microwave transparent layer such as Lexan provides a surface that is easily cleanable and acceptable for use in cooking food. The sides of the second tunnel can be pivoted to an opened position by hinges to provide easy access to the inside for cleaning.

Abstract: Apparatus and a method of producing fluid organic products from kerogen in situ in a body of oil shale by the application of alternating electric fields having a frequency between 100 kilohertz and 100 megahertz to heat the kerogen in the oil shale to a temperature in the range of 200.degree. C. to 360.degree. C. and to maintain the kerogen in this temperature range for a period of time sufficient to convert a substantial portion of the kerogen in oil shale to fluid organic products which may be collected through passages produced in the oil shale formation by flowing to a well bore having a collection sump.

Abstract: A moving target indicator system in which quadrature components of each range cell of returned target reflections are produced by phase comparison with the transmitted signals and compared by weighting three successive returns to obtain moving target differences for display.

Abstract: Parallel shifter architecture in an arithmetic unit of a digital computer for processing floating point mantissas. An arithmetic-logic unit (ALU) in series with shifting means functions in parallel with a barrel shifter. Both paths are executed simultaneously and the output of one path is selected for storage at the end of a microcycle based on machine status and the actual floating point numbers manipulated. This architecture provides a significant reduction in floating point addition execution time.

Abstract: A method of reducing angle noise in return signals to a monopulse radar having a radome is shown to consist of the steps of: (a) transmitting a pair of signals at frequencies equally spaced above and below the tuning frequency of the radome; (b) digitally processing the return signals to form the complex monopulse ratios of the return signals corresponding to each one of the transmitted signals; (c) determining, by comparing the magnitudes of each monopulse sum and monopulse difference signals with the level of respective predetermined sum and difference reference signals, whether or not angle noise is exhibited and whether or not the signs of the imaginary parts of the monopulse difference signals differ; (d) comparing, to a threshold level, the amplitudes of the monopulse difference signals of those return signals which exhibit angle noise to select return signals exceeding such threshold level and whose signs differ; and, (e) averaging the real parts of the complex monopulse ratios of the return signals wh

Abstract: A utensil for cooking or baking in a microwave oven. The utensil includes a partitioned tray and cover which are held in substantially fixed horizontal alignment by a microwave transparent base. The tray and cover are metallic and shield the interior there defined from microwave energy. A ferrite layer on the underside of the tray absorbs microwave energy to provide heat which conducts through the tray to the cooking compartments. The utensil can be used to fry and bake different foods simultaneous without intermixing the respective juices. Apertures in the cover provide for the escape of steam from the interior of the utensil.

Abstract: An X-ray generator system having control circuitry disposed for applying a selected voltage between cathode and anode electrodes of an X-ray tube and for sending a selected current through the tube during an X-ray exposure, the control circuitry including a voltage indicator network disposed for subtracting from the selected voltage anticipated losses in accordance with the level of selected current to indicate prior to the initiation of the X-ray exposure the actual voltage that will be applied between the cathode and anode electrode during the X-ray exposure.

Abstract: A solid state transmit/receive switching circuit is provided by a system which, in accordance with the invention, comprises a solid state relay which, when energized, causes an optically controlled resistor connected to an input terminal of a preamplifier of the receiver to change its resistance and hence the sensitivity of the preamplifier according to the transmitter transmission state.

Abstract: A distributed amplifier having a plurality of successively coupled field effect transistors with cascaded gate electrodes and cascaded drain electrodes. A first one of such transistors has the gate electrode thereof coupled to an input terminal adapted to receive an input radio frequency signal and the drain electrode thereof coupled to a dc drain electrode bias circuit. The last one of the successively coupled field effect transistors has the gate electrode thereof coupled to a dc gate electrode bias circuit and a drain electrode coupled to a radio frequency output terminal which produces an amplified radio frequency signal. The source electrodes of the plurality of transistors are coupled to ground. A drain bias voltage source is coupled between ground and the drain electrode bias circuit, such bias circuit providing a direct current path between such drain bias voltage source and the drain electrodes of the transistors.