Abstract: In a vertical deflection circuit for use in a television receiver or the like comprising a vertical oscillation circuit, a saw-tooth wave voltage generating circuit connected to the vertical oscillation circuit and a vertical deflection output circuit to which the output from the sawtooth wave voltage generating circuit is supplied, a capacitance circuit or a clamp circuit is advantageously incorporated in the vertical deflection circuit in order to eliminate bad effects on the interlaced scanning arising from the linearity correction loop.

Abstract: 1. In a frequency measuring system for measuring and indicating the frequency position of a signal within an extended band of frequencies, wherein said extended band of signals is divisible into a plurality of first sub-bands of equal extent and a plurality of second sub-bands of equal extent, the frequency extents of said first and second sub-bands being respectively different from each other, means for converting said signal to first signals only one of which occurs within each of said first sub-bands, means for further converting said signal to second signals only one of which occurs within each of said second sub-bands, means capable of measuring plural frequency locations within said plurality of first sub-bands for indicating the frequency location within said first sub-band of said first signal, and means capable of measuring plural frequency locations within said plurality of second sub-bands for indicating the frequency location within said second sub-band of said second signal.

Abstract: A television receiver includes conventional circuitry for detecting the information components of a received television signal. A cathode ray tube viewing screen is scanned by horizontal and vertical scanning circuitry. Low level pincushion correction circuitry imposes a bow-tie signal upon the vertical scan signal forming a composite signal. A series connected vertical yoke has a first terminal coupled to a vertical deflection amplifier and a second terminal connected to ground. The composite signal applied produces vertical scan and pincushion correction currents in the yoke. A tank circuit, resonant at the horizontal scan frequency, is interposed between the vertical yoke windings and a pair of shunting capacitors are connected in parallel with each of the yoke windings and the tank circuit to reduce yoke impedance to the pincushion correction components of the composite signal.

Abstract: A constant current sink for a cathode ray tube (CRT) display system is disclosed. The display system includes X and Y deflection coil current drive systems including parallel coupled constant current sinks that establish the deflection-determining current levels that flow through the X and Y deflection coils. Each constant current sink draws a fixed current level, and one or more are selectively switched ON, i.e., caused to draw a fixed current level through the deflection coil load from a first power supply, or OFF, i.e., caused to draw the fixed current level from a second power supply, to establish the desired electron beam position on the CRT. Means are provided for correcting for the pin-cushion, i.e., non-linear, effects associated with a flat CRT face.

Abstract: A push-pull common emitter deflection output stage energized by a relatively low direct voltage includes zener diode drive coupling to its input circuit for reducing crossover distortion. A diode in series with a deflection winding disconnects the output stage from the winding during a portion of the retrace interval to allow the retrace pulse voltage to rise to a relatively high direct voltage supplied through a switched transistor only during the retrace interval to reduce power dissipation in the output stage. Current feedback from the deflection winding to a driver stage during trace and retrace intervals accurately determines the retrace duration.

Abstract: In a cathode ray tube scanning system having a deflection yoke with horizontal and vertical deflection windings coupled to deflection current sources having horizontal and vertical scan rates, a top-bottom pin-cushion correction circuit includes a saturable reactor having a control winding coupled by a unidirectional conduction device to a flyback pulse signal source with a resonating capacitor coupling the unidirectional conduction device and control winding to a potential reference level and an output winding coupled to the current source at the vertical scan rate and shunted by a tuning means including a capacitor.

Abstract: A deflection circuit wherein coupling capacitors are placed in series with the transformed yoke impedance to reduce capacitance values and voltage ratings of these capacitors. One of the coupling capacitors also serves to integrate a centering current developed by a centering circuit, thereby providing for a relatively uniform direct current component through the yoke windings throughout each horizontal line of scan.

Abstract: Disclosed is a system for receiving a signal from a known direction and rejecting interfering signals arriving from other directions. The system makes use of a multibeam antenna having multiple ports corresponding to the multiple beams. The port corresponding to the beam in the direction of the desired signal is connected directly to a receiver while the outputs of the remaining antenna ports are used to cancel interfering signals arriving on their corresponding beams.

Abstract: High speed, spiral scan display apparatus capable of producing distortion free visual presentations from stored video data, and a method for preventing occurrence of visible distortion caused by switching transients in such apparatus. The visual presentations are generated by display writing means which traces a circular path on a display area. The radius of the circular path is periodically incremented to provide for scanning the entire display area. Visible distortion resulting from rapidly changing the path radius is prevented by blanking the display writing means for an interval of time immediately following each radius change. Data storage requirements are minimized by ordering and retrieving video data so that only data sequentially needed during unblanked intervals is supplied to the display writing means.

Abstract: A technique for making IFF Friend-Accept decisions based upon either receng T.sub.a correct replies in any consecutive sequence of W responses in a larger, predetermined number N of responses, or receiving a consecutive series of a predetermined number R.sub.a of correct replies. A Non-Accept indication is provided upon the occurrence of N interrogations before either T.sub.a correct replies are received in the group of W responses, or a consecutive series of R.sub.a correct replies are received. Target leading edge information is also derived from these determinations.

Abstract: A laminar flow electron gun employing a narrow, elongated cathode for forming a rectangular beam and a plurality of electrodes having narrow, elongated apertures cooperating with said cathode to draw electrons from said cathode and operate on the electrons to focus the rectangular beam onto a target by providing a parallel flow region adjacent said cathode, followed by a divergent flow region, in turn, followed by a convergent flow or focusing region.

Abstract: A transmission device of a radiographic navigation system for azimuth determination, in which an electronic rotating directional beam pattern and a static omnidirectional phase reference beam pattern are generated. For obtaining exact phase relationships between the signals required for generating the said beam patterns, phase control loops are included in the signal paths; in these loops the carrier wave frequencies are transposed to a lower frequency and the modulations are removed before phase comparison measurements are performed.

Abstract: A plurality of control plates is sandwiched between a cathode and a target to control the flow of charged particles such as electrons and ions between the cathode and the target. The cathode includes an elongated filament for generating charged particles such as electrons. A first electrode is positioned behind the filament with a second electrode having a positive potential interdigitated with the first electrode. The first electrode is divided into segments with a negative potential applied to those segments of first electrode where emission is desired from the elongated filament, and in those areas were emission is not desired those segments of the first electrode are switched sufficiently negative to cut off emission from the elongated filament. Each control plate has a plurality of apertures formed therein which are effectively aligned with corresponding apertures on the other control plates. The aligned apertures form beam channels.

Abstract: Seismic exploration method applicable to marine surveys. It involves making a dual spread of detectors which are spaced apart vertically. The signals received at one of the spreads are subtracted from corresponding signals received at the other spread. This eliminates horizontally travelling energy signals by cancellation.

Abstract: A self-regulating horizontal deflection system with feedback indicative of the magnitude of an unregulated voltage source and of load variations to pulse width modulate the output of the horizontal oscillator is shown. Separate turn-on and turn-off drivers are transformer coupled by separate primary windings to the horizontal output transistor to optimize the driver stage and conserve power.

Abstract: A plurality of control plates are sandwiched between a cathode and a target to control the flow of charged particles such as electrons and ions between the cathode and the target. Each control plate has a plurality of apertures formed therein which are effectively aligned with corresponding apertures on the other control plates. At least one input buffer plate and one output buffer plate are sandwiched between the control plates and the cathode and target respectively. The input buffer plate and the output buffer plate have a plurality of apertures formed therein aligned with corresponding apertures in the control plates. The aligned apertures form beam channels. The control plates have conductive electrodes thereon arranged at predetermined coded finger patterns. D.C. voltages are applied to the buffer plates to provide electron optic lensing and voltages are selectively applied to the control plate electrodes by switching circuitry to selectively open and close beam channels.

Abstract: Apparatus and method for providing electro-acoustic transducers of an acoustic surface wave device with an increased density of transducer elements. An increased density of transducer elements provides more accurate generation and reproduction of a desired frequency response above the design center frequency. By providing the sets of transducer elements which exchange signals by means of electro-acoustic surface waves with different densities of transducer elements, the transfer of undesired frequency components, introduced by the oversampled density of the transducer element sets, is reduced.

Abstract: In a vertical deflection output circuit comprising two transistors connected in push-pull configuration, the junction point of the two transistors is connected through a series circuit of a capacitor and a vertical deflection coil, with a first power source and also connected through a switch, which is turned on during the vertical retrace period, with a second power source whose voltage is higher than that of the first power source, and one end of a bootstrap capacitor is connected with the junction point while the other end of the bootstrap capacitor is connected with the base of one of the two transistors and also connected through a resistor with the second power source, whereby the bootstrap capacitor is prevented from being exposed to a voltage whose polarity is opposite to that of the voltage developed across the bootstrap capacitor due to the charging thereof.

Abstract: There is disclosed a method and apparatus for measuring electromagnetic conductivity within a medium to thereby derive a measurement of the rate of propagation of a magnetic field therein. If one then measures the return time of a pulse transmitted in the medium when a conductivity anomaly is encountered which creates a reflection, a magnetic diffusion radar can be calibrated. This technique enables one to measure the conductivity of a propagation medium such as salt water, earth or the like for any desired purpose such as determining the salinity of sea water or river water. More particularly, however, this enables one to make such a measurement in order to provide an electromagnetic anomaly detector such as is used in metal locaters, mine detectors, and in geophysical prospecting or exploration.

Abstract: In a radar PPI display, digital techniques are utilized to allow an operator to move the point about which the radial trace beam rotates to a point remote from the center of the radar viewing screen and including movement off the screen without actually moving the display beam off the screen. A sweep signal generator detects the location of the operator positioned off-center point from the settings of off-center controls and is responsive to radar range scale and antenna position signals to generate appropriate ramp deflection signals in the proper time sequence to accurately display a selected portion of the plan position indication upon the entire area of the viewing screen. A beam control circuit is responsive to the same signals as the signal generator and to a radar start pulse to determine the exact time the PPI display beam is to be turned on to display selected portions of the plan position indication.