Abstract: An automatic direction finding system utilizing the doppler principle for indicating the bearing of a radio transmission. The system includes an antenna array of three or more antenna elements equally spaced around a circular path. The antenna elements are connected to the input of a receiver through electronically controlled, variable attenuators which are individually adjusted at the same frequency but differing phases so that the array effectively simulates a single antenna element physically moving along a circular path at a fixed modulation frequency. The receiver includes a mixer-IF stage with the IF output phase locked to a reference frequency so that the absolute time delay through the IF stage is stabilized. The signal is then frequency demodulated, and the modulation signal is extracted by a narrow bandpass commutating filter.

Abstract: 1. An electron multiplier mosaic structure comprising:A plurality of alternate layers of uniform metallic and insulating material;An intermediate coating of metallic bonding material joining each adjacent layer in a solid unitary structure;A plurality of closely spaced apertures formed through said layers and arranged in a regular pattern on the opposite ends of said structure, each said aperture forming a continuous smooth interior surface between said ends, the metallic layer portions of said surface having secondary emission characteristics.

Abstract: The direction and/or distance between a fixed point and a vehicle or between two vehicles located on a common vehicle way are measured by an intermediate frequency interferometric technique wherein signals are transmitted from a single antenna to a receiver system comprising three equally spaced linearly arranged antennas. The technique encompasses determination of the path length differences between the transmitting antenna and each of the receiving antennas. The path length differences are thereafter employed to compute the distance to and/or direction between the transmitting antenna and the linearly aligned receiving antennas.

Abstract: An aircraft DME is receptive of a series of pulses the nature of which alternates between a series of random time spaced pulses and a series of uniform time spaced pulses, where the latter serve to identify the source of the pulses. A set-reset type of counter triggered by the decoded series of random pulses or by the decoded series of uniform time spaced pulses is thereafter continually advanced to a known count producing a gate signal which searches and locks onto the decoded series of uniform time spaced pulses by repeating the process. After a preselected number of repeats corresponding to successive uniformly spaced pulses, audio signals are produced so long as the uniform spaced pulses continue.

Abstract: The transducer functions as a capacitor to sense variations in inter-plate istances produced either by transducer displacement or by pressure. The capacitor plates include flexible rubber sheathing members having interior conductive surfaces spaced slightly from a conductive centrally-disposed metal plate. A pair of electrets are disposed one between each rubber surface and the central metal plate. Electrets are a battery replacement supplying a large electrostatic field. Opposite polarization of the electrets provides push-pull and directional capabilities. Like polarities, or the omission of one electrode, provide responsiveness both to pressure and to displacement. The central metal plate has sufficient mass to remain substantially stationary relative to the flexible movements of the rubber sheathing. Variations in the plate spacings produces variations in the capacitor output.

Abstract: A VHF omnirange receiver subject to extraneous amplitude modulation of the carrier close to the frequency of a variable phase VOR modulation signal with a subcarrier frequency modulated by a fixed phase signal at the frequency of the variable phase signal is adapted for elimination of the effect of the extraneous modulation. Amplitude modulation of the subcarrier is detected and amplified with phase reversal with amplification in an amount equal to the ratio of the carrier amplitude to the subcarrier amplitude to produce a cancellation signal. The cancellation signal is added to the composite received signal to eliminate the effects of unwanted modulation at the frequency on the carrier.

Abstract: In a vertical deflection circuit in which a capacitor in parallel with a pair of vertical deflection coils is charged by respective decreasing and increasing amounts of horizontal rate energy during respective first and second portions of a vertical scan interval for providing a substantially linear vertical sawtooth current through the vertical coils, a resonant circuit tuned to approximately the horizontal rate is coupled in parallel with the capacitor and a portion thereof is serially coupled with the vertical coils for providing a horizontal rate current component of such a phase in the vertical coils as to correct for top and bottom pincushion distortion.

Abstract: A circuit to correct for pincushion distortion and defocusing in a cathode-ray tube having electromagnetic deflection systems is disclosed. The circuit, which may be realized in monolithic integrated-circuit form, performs a mathematical function to predistort the deflection signal for each axis by the amount necessary to provide an undistorted display. The circuit also provides a signal to correct for the defocusing that occurs at the edges of the screen. The circuit may be readily adapted for use with cathode-ray tubes having different diagonal deflection angles, and with either flat of curved faceplates, by changing the values of two resistors.

Abstract: An automatic direction finder wherein a loop antenna is fitted within a combined handle and index rotatably pivoted at the center of a direction dial, a gear of a diameter large enough is fixed to said index and a pinion meshing with said gear is connected through a frictional power transmission with a direct current servomotor to which an automatically controlled output of said antenna obtained from the output of said antenna is given.

Abstract: A uni-directional laser amplifier system including a diverged beam having either a single unstructured pulse or a train of such pulses amplified to a very high power level over a long, folded amplification path. The beam emerges via a large, elliptical, cross-section aperture. The system includes two spaced rows of amplifying segments of elliptical and progressively increasing cross-sectional area with each segment having two polished non-parallel flat end surfaces with the front surface of each being anti-reflection coated and the rear surface having a laser mirror attached thereto or separated in conjunction with it by at least half the length of the laser pulse to be amplified. The segments are oriented an an angle of approximately 45.degree. to the length of its row and at an angle of about 90.degree.

Abstract: In a video signal receiving apparatus that employs tracking focus moire is eliminated by preventing the DC voltage of the focus electrode from increasing beyond the critical level at which moire will occur.

Abstract: Disclosed is an apparatus and process for indicating or measuring the frequency of an incoming signal of unknown frequency. The system includes a plurality of processing channels, each of said channels including a pair of oscillators offset in frequency coupled to a pair of harmonic generators for producing respective output signals harmonically related, wherein the fundamental frequency of said harmonic generators are correspondingly offset. A combination of mixers, filters, amplifiers, and frequency-to-voltage convertors are utilized in combination with logic comparator means for producing analog voltage signals representative of the unknown frequency. Examples of utilization and display of these analog signals are illustrated.

Abstract: This power supply detects the total power input to an image tube of the type utilizing microchannel plate electron multipliers in order to set the image output brightness. A current sensing resistor in the oscillator circuit provides a feedback potential in proportion to the total power demand of the image tube. This potential is applied to a transistorized circuit for limiting the input to the oscillator to a predetermined level.

Abstract: A centering circuit comprising a non-symmetrical conduction network and an integrating inductor in series combination is coupled to a deflection system between the junction of the S-shaping capacitor and the deflection windings and the junction of a winding of the high voltage transformer and its associated coupling capacitor, these junction points providing a relatively small but adequate voltage difference to energize the centering circuit with minimum deflection system power dissipation. The non-symmetrical conduction network comprises two oppositely poled diodes and a potentiometer. The adjustment of the potentiometer provides for a change of the magnitude and polarity of the average current flowing through the deflection winding during the trace interval.

Abstract: A temperature compensated acoustic surface wave device, such as a surface wave delay line is provided in which temperature compensation is provided by the deposition of an interdigital electrode structure on a substrate with an overlay film surface of piezoelectric material of a predetermined thickness. A double substrate arrangement is also disclosed in which the interdigital electrode structure is deposited upon the surface of a non-piezoelectric layer which in turn is placed upon the surface of a piezoelectric substrate.

Abstract: Apparatus for determining linear or angular measurements or measurements of positions on a planar or curved surface, which apparatus uses at least one delay element, such as a magnetostrictive element, for example, which is capable of supporting an accoustic wave signal. The one or more delay elements may be in the form of bands, rods, wires, planar or spherical structures, and the like, and can be arranged in various embodiments to provide linear or angular position information for single, dual, and multiaxis geometry. They can be used, for example, to provide single or multispeed resolver operation and three-axis attitude read-out. In preferred embodiments the apparatus uses phase measurement techniques so that high accuracy can be achieved.

Abstract: A satellite tracking antenna system for use on board ship as part of a maritime communications satellite terminal is disclosed. The system has a directional antenna which is continually trained in the direction of the satellite so as to receive signals therefrom and transmit thereto in spite of the continual rolling, pitching and turning movement of the ship as it travels along its course, even in heavy seas. The system includes a platform which is adapted to be mounted at the head of the mast of the ship. A servo control unit receives position and angular rate signals from roll and pitch sensors mounted on the platform, and serves to drive stepper motors through drive units therefor which counteract pitch and roll without the need for gyroscopic stabilization means and without requiring tachometers or other feedback control in the drive units so that the platform always remains level regardless of the pitching and rolling of the ship.

Abstract: A circuit arrangement for determining the distance of an aircraft from a VOR transmitter is connected with a VOR receiver which determines angular information of the VOR transmitter perpendicular to the radial position line with an accuracy of .alpha. degrees from one bearing shift to the next. The arrangement includes a pulse generator operable to produce counting pulses at a predetermined pulsing frequency of less than 1 Hz, preferably 0.95 Hz or 0.0549 Hz, and feeds the pulses to a counter. Apparatus responsive to a bearing shift applies the counting pulses to the counter and removes the counting pulses from the counter in response to the next bearing shift. A display is connected to the counter and calibrated in minutes for displaying the count to a pilot in order to indicate the flight time to the VOR transmitter at the airspeed employed in the measuring operation.

Abstract: First pulses timed for enabling conduction of a first switch in a two-switch deflection system are delayed and combined with retrace pulses obtained from the system for forming second pulses suitably timed for enabling conduction of the second switch.

Abstract: Methods and apparatus for identifying the source location of acoustic emissions generated within an acoustically conductive medium. A plurality of acoustic receivers are communicably coupled to the surface of the medium at a corresponding number of spaced locations. The differences in the reception time of the respective sensors in response to a given acoustic event are measured among various sensor combinations prescribed by the monitoring mode employed. Acoustic reception response encountered subsequent to the reception by a predetermined number of the prescribed sensor combinations are inhibited from being communicated to the processing circuitry, while the time measurements obtained from the prescribed sensor combinations are translated into a position measurement representative of the location on the surface most proximate the source of the emission. The apparatus is programmable to function in six separate and five distinct operating modes employing either two, three or four sensory locations.