Abstract: An opaque open-ended cylindrical tube, with a flange on one end, has its other end connected to a surface of a platform with the axis of the cylinder normal to the surface. When rays of the sun are substantially normal to the surface, a lens causes a concentrted illumination of a group of tracking photocells carried on the surface within the cylinder. In response to the concentrated illumination, the tracking photocells provide signals that cause the platform to rotate in a direction that maintains the surface substantially normal to the rays of the sun. Additionally, outside of the cylinder and adjacent thereto, a group of acquisition photocells are shielded by the flange from the sun when the rays thereof are substantially normal to the surface. When there is a large angle between a normal to the surface and the rays of the sun, the acquisition photocells provide signals that cause the platform to rotate in a direction that reduces the angle.

Abstract: Circuit to apply an offset voltage to be added to a charge storage signal depositing a charge on a radially swept charge storage surface so that the charge storage signal is a minimum at the center of the surface and a maximum at the outer edges of the sweep. This reduces or eliminates the charge integration in the area where the sweep lines converge.

Abstract: An output coaxial cavity for high power electron tubes is described in which the output coupler is directly connected to an intermediate coaxial conductor of the coaxial cavity at a distance from the tube that is greater than one-quarter wavelength and less than one-half wavelength over the tuning range of the cavity. The intermediate coaxial conductor is spaced between and concentric with an inner conductor and an outer conductor of the coaxial cavity. A first shorting stub is positioned between the inner conductor and the intermediate conductor and a second shorting stub is coupled between the intermediate conductor and the outer conductor. The positions of the shorting stubs are arranged to resonate the cavity at the desired tuning frequency.

Abstract: A truncated conical member of conductive material is mounted forward of a pair of crossed dipoles, the legs of which are inclined toward a reflector. The pair of dipoles cross orthogonal to each other at the dipole centers with the dipole halves being fed with equal power in the relative phase rotation of 0.degree., 90.degree., 180.degree. and 270.degree..

Abstract: A multimode coupling system for coupling symmetrical waveguide mode signals and two or more tracking asymmetrical waveguide mode signals includes a funnel-shaped coupler with a plurality of coupling apertures located in the side wall thereof. A first four of these side wall apertures lie in a first common plane at a given distance from the small aperture end of the coupler. A second four of these apertures lie in a second common plane a second given distance from the small aperture end of the coupler. A first coupling circuit is provided between the first group of side wall apertures and an asymmetrical mode terminal, and a second coupling circuit is provided between the second four apertures in the second plane and a second asymmetrical mode terminal.

Abstract: A system, which selects the most desired signal from similar signals provided by two or more radio receivers, includes a signal quality detector and a comparator for each of the signals. Each detector provides an output signal level indicative of the quality of the signal to which that detector is responsive. A ramp signal is coupled in common to each comparator, and the comparator that first senses a detected output signal level equal to the ramp signal level causes the corresponding received signal to be gated to the output of the system.

Abstract: A measurement of the group delay and the amplitude response of the upper and lower sidebands of a transmitter is provided by amplitude modulating with a tone a video signal that modulates the transmitter carrier. The frequency of the video signal is changed to provide a search or coverage over the frequency bands of the upper and lower sidebands. A mixing and frequency selection are performed at the transmitter RF output to select a particular upper and lower sideband. An envelope detector demodulates the tone that is amplitude modulated on the selected sideband signal. The amplitude of this detected signal is indicative of the amplitude response and the phase of the detected signal relative to a reference phase is indicative of the group delay at the selected sideband signal.

Abstract: Universal/Assigned Night Answering system incorporated in an EPABX system permits any telephone station to answer a universal incoming call or an associated assigned incoming call from incoming trunk line while retaining the ability to initiate calls to other telephone stations within the EPABX system or to outgoing trunk lines. A UNA/ANA module is provided using a standard half-register for UNA operation and circuitry for ANA, the module also being coupled to the common control line and having its own vertical line in the switching matrix.

Abstract: A binary quantized TV video signal of any single one of a plurality of different symbols is generated and then successively sampled at respective dot positions thereof, with the binary value of each sample being stored at a corresponding dot position of an individual one of a plurality of dot matrices of the memory, that dot matrix being located at a preselected address location of the memory. The whole process is under the control of a programmed sequence control generator which is capable of automatically controlling the loading of each of the plurality of different symbols, in turn, into its own preselected address location dot matrix of the memory.

Abstract: A high repetition rate injection laser modulator wherein a DC bias voltage is applied across a serially connected forwardly-poled-injection laser and carrier-injected avalanche device. The carrier-injected avalanche device generates a current pulse in response to additional carriers injected into the device by a trigger pulse applied across the control junction of the avalanche device. An offset bias is provided across the control junction to remove built-up charges at the junction interface to provide for high repetition rate operation. The current pulse is of sufficient magnitude to effect pumping of the injection laser, the injection laser thus emitting a corresponding pulse of coherent light.

Abstract: Spacecraft nutation caused by applying propulsive forces to a spacecraft along an axis which does not pass through the spacecraft's center of gravity is eliminated by a signal responsive control system which operates the propulsive forces for a predetermined time period which corresponds to an integral number of nutation periods.

Abstract: A stable, wide-deviation linear voltage controlled frequency generator including a conventional voltage controlled oscillator (VCO) in a control loop which linearizes the output frequency of the VCO. The control loop includes a crystal oscillator and a digital frequency discriminator. The digital frequency discriminator compares the frequency of the VCO output signal with a stable fixed frequency signal from the crystal oscillator to generate a feedback control signal for the VCO. A novel digital frequency discriminator comprising a digital one shot and a low pass filter is disclosed.

Abstract: An analog to digital converter includes a plurality of current sources selectively coupled to a capacitor for charging the capacitor from a reference level with a first reference current in a fixed time period and for discharging the capacitor with a second reference current to the reference level. The capacitor is then charged from the same reference level with a current derived from an unknown voltage source for the same period of time as in the case of the first reference current and discharged to that reference level at the same discharge rate by discharging with the second reference current. The difference between the respective times it takes the capacitor to discharge to the reference level in the two discharge cycles is determined and represents the amplitude of the unknown voltage. Suitable display means provide a digital representation of this amplitude.

Abstract: A broad-band microwave amplifier including a semiconductor TRAPATT diode generating a microwave signal at its fundamental, second and third harmonic frequencies. Energy is extracted at the second harmonic frequency and a certain impedance loading is provided at the fundamental and third harmonic frequencies by an open-ended tapered microstrip idler circuit connected in parallel with the diode. The tapered idler circuit also provides a predetermined relatively small rate of change of impedance with respect to frequency changes to obtain a wide instantaneous bandwidth of the amplifier.

Abstract: A diode package comprising a compressible dielectric member having an aperture extending through its two major opposite surfaces. An electrically conductive lid is attached on one of the major surfaces of the dielectric member and an electrically conductive base is attached on the other surface. A semiconductor diode having two terminals oppositely situated is soldered with one diode terminal to the base within the aperture of the dielectric member. The lid is further soldered to the other diode terminal subsequent to the compressible dielectric member being compressed an amount sufficient for the lid to make an electrical connection to the other diode terminal.

Abstract: An interferometer, that simultaneously employs two phase-quadrature reference beams of coherent light which interfere with a signal beam of coherent light reflected from a spot of a displaceable signal mirror insonified by an ultrasonic wave, permits an output signal to be derived which is proportional to the sum of the squares of the ultrasonic frequency component of the interference between the signal beam and each respective one of the reference beams. This output signal is inherently substantially proportional to the intensity of the ultrasonic wave then insonifying the spot of the signal mirror and independent of random phase drift and environmental vibrations in the interferometer. The interferometric technique of the present invention, which permits the ultrasonic wave to be in the form of pulse bursts of only a few cycles so that the output signal can be range-gated, is suitable for use in an ultrasonic-wave measurement and image display system.

Abstract: By coupling light from a coupling portion of a thin fiber core to a planar waveguide film through the thickness of the substrate supporting the film, sufficient spreading by diffraction takes place in the light traveling through the thickness of the substrate to provide an aperture at the film large enough to permit light coupled into the film from the substrate to have a substantially plane wavefront.

Abstract: A solid cylindrical recording medium is axially rotatable within a cavity in a transparent block, the medium and the cavity being complementary in shape. The medium and the block have substantially equal indexes of refraction whereby the medium does not refract light transmitted thereto through the block. Transmitted to the medium (through the block) is an object beam, representative of an image, and a reference beam, whereby the medium is exposed and a volume hologram of the image is recorded. A multiplicity of volume holograms of images may be recorded by rotating the medium with respect to the reference beam after each of a multiplicity of exposures.

Abstract: A dual- band Cassegrain antenna system operable at any polarization is described wherein the hyperbolic subreflector is made to reflect signals at a first band of frequencies and to transmit or pass signals at a second lower band of frequencies. The hyperbolic subreflector according to one embodiment is a square grid mesh with conductive rings centered along the connecting legs of the square grid mesh. The rings are approximately one-third wavelength in diameter at the first band of frequencies and act capacitively at the second lower band of frequencies. The inductive reactance provided by the conductive connecting legs of the grid mesh together with the capacitive reactance provided by the rings at the lower band of frequencies causes the subreflector to transmit signals at the second lower band of frequencies.