Abstract: A color picture tube of an in-line type comprises means for deflecting beams of electron emitted from electron guns of the in-line type aligned horizontally such that for the horizontal deflection, the central beam is subjected to a greater deflection than side beams and for the vertical deflection, the side beams are subjected to a greater deflection than the central beam. Two vertical magnetic pole piece plates which are long vertically and thin horizontally are so disposed as to sandwich the central beam near the outlet of the central electron gun in order to weaken horizontal deflection magnetic field acting on the central beam, whereby a portion of the horizontal deflection magnetic flux acting on the central beam is absorbed by the two magnetic pole piece plates. The vertical deflection magnetic field is almost not affected by these vertical magnetic pole piece plates.

Abstract: In conjunction with an AC plasma display panel a light detecting pen is employed to designate coordinate points on the panel. Circuitry is employed to scan the electrodes of the panel with sustain voltage pulses at predetermined intervals and determine the coincidence of a selectively applied sustain voltage pulse with light detected by the light pen to indicate the location of the light pen with respect to the panel. A negative scanning method is also disclosed wherein coincidence between a sustain voltage pulse which is selectively not applied and the non-detection of light indicates the location.

Abstract: Apparatus is responsive to an alternating signal which exceeds a first level, V.sub.L, and within a given time, t, exceeds a greater second level, V.sub.H, by causing a signal manifestation pulse to issue. The apparatus is responsive to a signal which does not exceed V.sub.H within time t after exceeding V.sub.L causing disablement of the circuit.

Abstract: An aircraft proximity warning indicator incorporating an RF receiver, optical sensor, and display is described which may receive an RF signal followed by an optical radiation pulse from another aircraft where the received RF signal is used to control the optical sensor and display so that it senses and displays the optical radiation pulse.

Abstract: The invention relates to arrangement for detecting the presence of echos for a multi-range-gate radar system.The signal A from a gate is combined with a signal B from one or more neighboring gate. This combination is performed by means of an operator which supplies signals S.sub.1 = A + k.sub.1 B and S.sub.2 = k.sub.2 (A - k.sub.1 B), where k.sub.1 and k.sub.2 are complex coefficients. A demodulator receiving S.sub.1 and S.sub.2 supplies a signal proportional to the cosine of the phase between S.sub.1 and S.sub.2. Said cosine signal is sampled, filtered and compared to a threshold. When exceeding said threshold the output signal indicates that an echo signal is received.

Abstract: A first glass substrate supports a plurality of electrodes arranged in concentric circles. A second glass substrate supports a plurality of shift electrodes arranged radially. The substrates are positioned face to face with a specified space between them filled with an ionizable gas. The radially arranged shift electrodes are periodically connected to common buses each connected to a corresponding one of a plurality of shift driver circuits equal in number to the buses. At least one of the shift electrodes is selectively connected to a write driver circuit and to one of the shift driver circuits. When the one of the shift electrodes is energized by a signal from the write driver circuit, discharge spots are generated at the intersection of the one of the shift electrodes and the concentrically arranged electrodes.

Abstract: A pulse of energy including atomic, thermal or electromagnetic radiation produced by a source such as an electron or atomic beam, laser, electrical or optical means is applied to a generator. The generator includes a body of material adapted for acoustic vibration. An energy absorbing layer is in intimate acoustic contact with the body of material so that acoustic vibrations generated in the absorbing layer are transmitted to the body of material. The surface of the absorbing layer opposite to the body of material is acoustically clamped in position by a solid clamping medium.

Abstract: A low PRF pulse doppler radar system utilizing a VIP digital filter bank signal processor to suppress echoes from terrain, rain, and chaff, and pass echoes from aircraft moving at higher speeds is disclosed.Each of a plurality of VIP filters individually provides high attenuation to undesired signals over designated frequency bands, the width of which are a large fraction of 1/T.sub.av where T.sub.av is the average interpulse period. Little or no attenuation of desired signals having doppler frequencies greater than 1/T.sub.av occurs. The outputs of the plurality of filters are desensitized to prevent false alarm from clutter, and the presence of a desired radar pulse echo is determined by a comparison with a threshold level.

Abstract: An aircraft ground movement monitoring system is provided similar to that described in co-pending U.S. patent application Ser. No. 608,214, now U.S. Pat. No. 4,109,248, that makes use of an aircraft's existing SSR transponder in a hyperbolic selective interrogation technique to monitor an aircraft's position on an airfield in which, in order to overcome the problems particularly involving spurious mode C (height) interrogations that arise in long base-line systems, it is arranged that transponders that would be spuriously interrogated are interrogated first and that the required transponder is interrogated before the already interrogated transponders have finished replying.

Abstract: A monopulse radio direction finding and tracking system having the capacity of detecting the presence of multiple radiating sources within the effective beamwidth of the monopulse antenna and causing the monopulse antenna to move toward and align its boresight with one of the multiple sources. Signal processing is provided that implements an algorithm based on the amplitudes and absolute magnitudes of signals from a receiver sum channel, elevation and azimuth difference channels, and elevation and azimuth angular error channels. The algorithm utilizes the differences in the ratio of signals present in these channels when a single radiating source is present and when multiple sources are present. Steering control circuits are provided that bias the azimuth and elevation antenna steering servo system to cause the antenna to align its boresight with one of such multiple sources.

Abstract: A navigational plotter in which a geographical map or chart has marked thereon lines of position corresponding to the Omega or Loran navigation system aids, for example. The intersections of the lines of position with a base line on the chart are recorded in coded form on a separate strip of the chart. The coded signals on the chart strip are read out by the plotter, so that the position of the marker or indicator of the plotter may be read out directly in terms of lines of position corresponding to Omega or Loran systems. The marker or indicator of the plotter may also be positioned directly from information obtained in terms of Omega or Loran lines of position.

Abstract: A coherent demodulator for recovering the phase modulation from an input intermediate frequency signal includes a phase locked loop having switchable frequency and phase detectors. During initial acquisition the phase locked loop frequency is adjusted to be equal to the input intermediate frequency by comparing the loop frequency with the input frequency in the frequency detector and using the resulting error signal to adjust the loop frequency. After acquisition the phase detector maintains the loop frequency phase locked to the input frequency by now using the resulting error signal to adjust loop frequency phase, the error signal from the phase detector being the recovered phase modulation. A second control loop includes a narrow pass filter tuned to the desired frequency of the loop frequency. The error signal from the second loop is summed with the first mentioned error signal to precisely maintain loop frequency.

Abstract: Disclosed is a device for spreading chaff payloads for radar interference comprising a cartridge having a number of oblong cells in which chaff bundles may be displaced towards the output end of the cartridge. The cells are arranged as units each having a displacement mechanism which is selectively operable. Each unit may be shaped as a self-supporting module preferably having three tube-shaped cells.

Abstract: A vibratory seismic energy source capable of generating significant energy over a broad frequency band. The vibrating baseplate and associated structure are designed for minimum size and weight, while retaining the structural strength to permit high actuator forces. The weight of the transport vehicle is applied to a substantially horizontal hold-down plate that is interposed between the piston-cylinder assembly and the baseplate. This horizontal plate is coupled to the baseplate through resilient means having compliance such that dynamic motion of the baseplate is decoupled from the hold-down plate and transport vehicle.

Abstract: A synthetic aperture radar in which radial motion compensation is provided by a monopulse null tracking loop which tracks the null position of a stabilized monopulse antenna, and in which tangential motion compensation is provided by a tangential velocity measurement loop which tracks the cross-over angle of the monopulse antenna pattern. Since the motion compensation for the synthetic aperture radar is made in relation to a stabilized monopulse antenna, the imaging process for the synthetic aperture radar may be controlled in response to the angular scan rate of the antenna.

Abstract: A control system for an aircraft radio-navigation installation having forward-looking and rearward-looking antennas. The system provides the usual diversity reception facilities of "hunting" and then locking on to one antenna when an acceptable signal is received and in addition it selects the appropriate antenna with reference to the velocity and attitude of the aircraft relative to a ground transmitter even if the signal received on the inappropriate antenna is acceptable.

Abstract: Determination of the pointing accuracy of a commutated scanning beam aerial is effected by monitoring the phase of the signal received at a point where, at all times during its operation, a field is established by the aerial. The phase of the sampled signal is observed by comparing it with a second signal which is sampled elsewhere in the field region or which is derived from the RF signal source of the aerial. This comparison can be effected by heterodyning the two signals. Pointing accuracy is determined by comparing the signal produced by the heterodyning with a pre-recorded signal typifying that experienced when the pointing error is zero. The technique is applicable to commutated torus aerials and to aerials incorporating a linear array of radiators to which power is supplied from a commutated array of excitation elements via an electromagnetic lens.

Abstract: An azimuth correlator architecture is defined wherein a number of serial range-line buffer memories are cascaded such that the output stages of all buffer memories together form a complete and unique range bin in the azimuthal dimension at any given time. A range bin is automatically read out of the last stages of the registers in parallel on a range line sample-by-sample basis for subsequent range migration correction and correlation. Range migration correction is performed on the range bins by effectively varying the length of a delay register at the output of each range-line buffer memory. The corrected range bin output from the delay registers is then correlated with a Doppler reference function to form an image element on a real-time basis.

Abstract: A switched television pincushion correction circuit uses a controllable switch including an SCR gated at the horizontal deflection rate. The gating signal is a horizontal rate pulse which is duration-modulated at the vertical rate. A gating pulse generator includes a source of rectified mutually inverted vertical sawtooth signals. An offsetting circuit generates from the rectified signals two vertical rate signals offset from each other by a fixed amount. The offset signals are summed and the sum signal is used to modulate a horizontal-rate ramp-on-pedestal signal in order to generate the duration modulated SCR gating signal.

Abstract: An antenna element for use in the nose section of a small missile is disclosed. The antenna element includes a ground plane and a pair of end fed radiating elements, the free ends thereof being fastened to ground plane. With such arrangement the antenna element fits compactly within the nose section and the ground plane provides a heat sink and structural support for the radiating elements.