Abstract: A generator suitable for producing a sawtooth and a parabolic signal for the line or field deflection in a television system. The generator is provided with two dc coupled, series-connected difference amplifiers with feedback, which are each part of an associated integrating circuit. Via a peak detection circuit the output of the second difference amplifier is connected to the non-inverting input of the first difference amplifier. The second integrating circuit has been rated in such a way that the peak-peak value of the parabolic signal is half that of the sawtooth signal, while independent of the peak-peak value adjustment the ground potential is present in both signals in the center of trace; consequently there are no centering difficulties.

Abstract: A horizontal deflection circuit comprises a deflection winding, an output deflection circuit for generating deflection current and retrace pulses, an oscillator and driver circuit for providing drive signals to the output deflection circuit, a frequency and phase control circuit for synchronizing the deflection current with incoming sync pulses, and a correction circuit. The correction circuit corrects for variations in initiation of retrace which are not adjusted by the frequency and phase control circuit, such as caused by variations in storage time delay of an output transistor. The correction circuit includes a sawtooth generator for obtaining a sawtooth voltage from a retrace pulse and a peak separator to which the sawtooth voltage is coupled for generating voltage pulses for providing a correction voltage to the oscillator and driver circuit.

Abstract: A Doppler Radio Navigation beacon with multi-element reference and main commutated arrays. The reference signal is programmed among the reference array elements irregularly to provide spatial diversity to the reference signal to eliminate or substantially reduce reference masking effects in certain multi-path situations (as observed at a remote receiving station such as on an aircraft on landing approach deriving angle information from said beacon). A similar irregular element excitation program is imposed on the normal array preserving coherence in the relative radiator movement (during commutation) between reference and main arrays.

Abstract: A raster distortion correction circuit for correcting both pincushion distortion and trapezoidal distortion of a raster on a cathode ray tube. A parabolic-shaped signal and a sawtooth-shaped signal, both having frequencies equal to the vertical deflection frequency, are supplied to the correction circuit. The amplitude and polarity of the sawtooth-shaped signal is selectively adjusted, and the adjusted sawtooth-shaped signal is combined with the parabolic-shaped signal and supplied to a current modulator. A horizontal deflecting current flows through the modulator and is thus modulated by the combined parabolic-shaped signal and adjusted sawtooth-shaped signal, the modulated horizontal deflecting current being supplied to a horizontal deflection coil included in the horizontal deflection circuit for the cathode ray tube. The parabolic-shaped signal component corrects the pincushion distortion and the adjusted sawtooth-shaped component corrects the trapezoidal distortion.

Abstract: A spectrum reuse antenna system is described for transmitting orthogonally polarized RF waves at one frequency band to a satellite and for receiving orthogonally polarized RF waves from a satellite at a second frequency band through a common antenna. A local generator provides a first control signal which varies as a function of the typical rotation of the polarization of a transmitted wave at the one frequency band travelling through the ionosphere. The local generator also provides a second control signal which varies as a function of the typical rotation of the polarization of a received wave at the second frequency band travelling through the ionosphere. A driven means responsive to the first control signal causes a rotation of the polarization of the transmitted waves to correct for Faraday rotation in the ionosphere and a driven means responsive to the second control signal causes rotation of the polarization angle of the antenna system for the received waves to correct for the Faraday rotation.

Abstract: In a CRT display exhibiting a Rho-Theta format where certain of the lines would normally extend beyond the edges of the CRT screen, feedback signals from at least a deflection coil are used to terminate display lines at the edge of the screen and to initiate immediate retrace. Compensation is applied to at least a deflection voltage to compensate for display line bunching caused by unequal scan line times.

Abstract: A passive transponder sensitive to electromagnetic pulses received in the form of surface acoustic waves. The device utilizes a plurality of interdigital transponders each consisting of a metallic deposit on a piezoelectric substrate and serving as an electrode. Transponder deactivation and energy interruption means provide programability and coding.

Abstract: Apparatus for detecting an error condition in a deflection circuit of a cathode ray tube, the deflection circuit being of the type wherein a periodic retrace signal is generated, including a filter coupled to the retrace signal generator and normally non-responsive to the retrace signal. In the event of an error condition, the retrace signal is provided with higher frequency components which are transmitted by the filter. An output signal generator is coupled to the filter to produce an output signal in response to the signal components transmitted by the filter. In one embodiment, the deflection circuit is the horizontal deflection circuit of a CRT wherein the retrace signal is used to produce the high voltage for the CRT. In this embodiment, the output signal is used to vary the repetition frequency of the horizontal oscillating signal applied to the deflection circuit so as to correspondingly change the amplitude of the retrace signal and, thus, to reduce the magnitude of the high voltage.

Abstract: This disclosure depicts an electron gun for use in a color cathode ray tube of the small neck, shadow mask-type. The gun includes an extended field lens for generating a cluster of electron beams converged and individually focused at the screen of the tube. Three main focus lens means are situated on lens axes which are mutually parallel and parallel to a gun central axis. At least two of the lens axis are off-axis with respect to the gun axis. The focus lens means has for each beam at least three electrodes including a focus electrode for receiving a variable potential for electrically adjusting the focus of the beam. In succession down-beam, there are at least two associated electrodes having potentials thereon which forms in the gaps between adjacent electrodes significant main focus field components. To adjust beam focus, the strength of a first of these components is controlled by adjustment of the voltage received by the focus electrode.

Abstract: A sidelobe cancellation system in which the cancellation loop is insensitive to both target and clutter signals is disclosed including a correlator wherein the video inputs thereto are timegated to exclude all but maximum range signals and the gated video is further bandpass filtered to exclude the mainlobe and first sidelobe of the radar video spectrum.

Abstract: An improved circuit for suppressing the occurrence of a sharply-focused light spot on the screen of a television receiver when the set is turned off is described. A normally conductive, controllable electronic switch is normally effective to maintain the brightness control grid of the cathode ray tube blocked, such switch assuming its non-conductive state only during the presence of the normal forward sweep portion of the deflection voltage to impart a positive step in voltage to the control grid to permit the now-moving light spot to be visible on the screen. During the flyback portion of the deflection voltage, or equivalently during the disabling of the TV set so that no forward sweep voltage is present, the controllable switch reverts to its "fail-safe" conductive condition to immediately restore the negative blocking voltage on the control grid to inhibit the beam current and thereby the formation of the now-stationary light spot.

Abstract: An interdigital electrode transducer mounted on an acoustic surface wave propagating medium having an output proportional to an Nth order derivative of the surface acoustic waves propagating in the medium. The Nth order derivative, where N is any real, positive number, is obtained by using a finite difference approximation. The transducer finger pairs are biphase coded and amplitude weighted in order to detect the proper combination of signal differences for the approximation and thereby indicate the desired derivative.

Abstract: An accelerometer located on the pad of a vibratory seismic source provides a signal for comparison with the sweep signal which controls the vibrator. The error function representing the difference between the phases of these two signals is used to adjust the phase of the vibrator so as to maintain the vibrator in synchronism with the sweep signal. Prior to comparison with the sweep signal, the accelerometer output is conditioned by a tracking bandpass filter having its center frequency slaved to the instantaneous sweep frequency. Those components of the accelerometer output signal having a frequency equal to the instantaneous sweep frequency are passed by the bandpass filter and are subjected to approximately 0.degree. phase shift through the filter.

Abstract: A vertical deflection circuit for television receivers or the like which has an output stage of single-ended push-pull amplifier configuration is provided with a power supply circuit which includes a rectifying circuit connected between a D.C. voltage source and the output stage for rectifying an external A.C. voltage fed thereto to produce an additional D.C. voltage. The power supply circuit supplies a first D.C. voltage from the D.C. voltage source to the output stage during the first half of a trace or scanning period and supplies a second D.C. voltage, obtained by adding the additional D.C. voltage to the D.C. voltage from the D.C. voltage source, to the output stage during the second half of the trace or scanning period and during the retrace period.

Abstract: A recurrent digital sweep signal starts an integrator fed by a constant current. The integrator includes push-pull Darlington stages, which act as alternately conducting controlled current sources for split deflection coils outside the integrator feedback loop. A phase shifter provides arcsine correction. A time-out circuit avoids excessive dissipation if the sweep signal should be lost.

Abstract: Three mutually orthogonal radiating antennas each transmit electromagnetic radiation to three mutually orthogonal receiving antennas. The transmitted electromagnetic radiation carries data characterizing the phase of the electromagnetic radiation. Measurement of the three transmitted signals as received by the set of three orthogonal receiving antennas produces nine parameters which, in combination with one known position or orientation parameter, are sufficient to determine the position and orientation parameters of the receiving antennas with respect to the position and orientation of the radiating antennas.

Abstract: A system involving a mechanically or electronically scanned beam of electromagnetic energy and separate antenna means for transmitting a phase reference signal. A remote receiving station, such as on-board an aircraft on landing approach, is able to process received signals coherently to take advantage of the increased accuracy available in such processing.

Abstract: The tracker tracks on a center of contrast on a selected target while trang gates are adjusted automatically to fit the target contrast area's shape and size. The appropriate bright or dark contrast detector is adjusted to allow discrimination of the target contrast from its background, thus allowing a tracking window to encompass the selected contrast area. Orthogonal error signals are provided for servoing a vidicon camera to maintain the viewed field centered on the target.

Abstract: In seismic delineation of sedimentary section below the surface of a seismic energy propagation medium, a new use for an old article is disclosed. It includes a basic method for generating and shaping a seismic energy pulse comprising (1) generating a first energy pulse downwardly through the shortest distance to a point at the lower end of a vertical straight explosive material for forming a compressional forward portion of the seismic energy pulse, and (2) generating a second energy pulse later to form a rarefactional aft portion of the seismic energy pulse. By varying the length of the explosive material the lengths of the forward and aft portions are varied for controlling the shape of the seismic energy pulse, and by varying the position of the point of ignition of the linear explosive material, additional shaping of the seismic energy pulse results.

Abstract: The present invention relates to a method of and apparatus for indicating e geographical position of a piloted vehicle equipped with a computer, the method comprising the steps of using a geographical map or a portion of map, approximately orientated, without regard to its method of folding and its dimensions; identifying and transmitting to the computer at any desired moment, basic information such as reference of alignment on a meridian of the map-references of magnetic declination and scale of said map, co-ordinates of at least one radio-navigation transmitter chosen on the map, co-ordinates of at least one objective to be reached on the map, co-ordinates of at least one possible intermediate point on the route; indicating on said map at any instant under the control of the computer which also receives the variable radio-navigation information from the transmitter selected, the geographical position of the vehicle, the above identification and indication steps being effected by the use of a single organiza