Abstract: A photoelectric touch input apparatus comprises a frame placed in front of the display surface of a display device, a plurality of light-emitting elements mounted on the frame in a row along one side of a central opening of the frame to produce a plurality of light beams in parallel spaced relationship, a plurality of photosensitive elements mounted on the frame in a row along the opposite side of the opening and aligned with the light-emitting elements to receive the light beams, a transparent flat plate arranged between the display surface and the light beams and resiliently supported on the frame to be moved toward the display surface by pressure of an object touched thereto, a comparison circuit associated with the photosensitive elements to produce a first output signal indicative of the position of the object when it interrupts one of the light beams, a plurality of switches mounted on the frame and associated with the flat plate to produce a plurality of second output signals therefrom in response to m

Abstract: In order to reduce the amount of internally scattered radiant energy in an optical system having a collecting optical chamber and a secondary optical chamber, a moving aperture device is positioned in a first focal plane between the chambers; the aperture device has a continuous moving metal band that has staggered slits therein. The band is sprocket driven and cryogenically cooled to reduce thermal emission. The band can be synchronized with other scanning detectors in the optical system such as one might find in an infrared telescope used in outer space.

Abstract: An autocollimating alignment telescope automatically turns a lamp on in the autocollimating operational mode, and automatically turns the lamp off in the alignment telescope operational mode. The telescope has reticles which are replaceable in the field, as well as eyepiece and lamp housings whose mountings are interchangeable. The telescope also has an assembly for preventing jamming of the traveling lens assembly of the telescope, as well as independently operable coarse and fine adjustments for the traveling lens assembly.

Abstract: The generation waveforms is accomplished using: a computer, two random access memories (RAM), a digital-to-analog converter (DAC), two modulators, two oscillators, and a multiplier. The computer inputs a set of digital waveforms and a first control signal into the first RAM which, when directed, conducts them to the DAC. The DAC converts the digital waveform to an analog waveform, and conducts the analog waveform and the first control signal to the first modulator. The first modulator produces an output signal by single sideband (SSB) modulating an intermediate frequency carrier from the first oscillator with the analog waveform when directed to modulate by the first control signal, and outputs the analog waveform otherwise the multiplier increases the bandwidth of signals from the first modulator by multiplying its output signal. The output of the multiplier is received by the second modulator.

Abstract: A quasi-resonant random access deflection system includes a biresonant, bidirectional deflection circuit connected to the deflection yoke of a display monitor picture tube and a control circuit connected to the deflection circuit and being operable to generate signals to actuate the deflection circuit so as to cause, via the magnetic fields of the deflection yoke, selected movement of the electron beam of the picture tube along a bidirectional path and stopping of the beam at any position along the bidirectional path.

Abstract: A transistor modulator for use in a circuit for processing video and sound signals of a video game so as to produce a composite output signal for application to the antenna input of a television receiver to produce a display of such video game. The modulator comprises an MOS transistor having a source electrode, a drain electrode and two gate electrodes. The video and sound signals and a VHF carrier signal are applied to respective ones of the two gate electrodes and either of the source and drain electrodes. The MOS transistor produces the composite output signal across an impedance which is connected to the other of the source and drain electrodes.

Abstract: A phase-locked loop is constituted by a controllable oscillator coupled through a phase detection arrangement and a low-pass filter to receive an input carrier applied to a signal input of the phase detection arrangement. In order to decrease the phase synchronization between a carrier locally generated in the loop and an input carrier, an unwanted DC offset generated during phase detection is reduced. The phase detection arrangement has first, second and third cascade-coupled mixer stages. An auxiliary mixing signal is applied from a signal generator to the first and third mixer stages. An input of one of the first and second mixer stages is coupled to the signal input of the phase detection arrangement and an input of the other of the two last-mentioned stages is coupled to an output of the controllable oscillator. The low-pass filter has a cut-off frequency lower than the fundamental frequency of the auxiliary mixing signal, and the fundamental frequency is lower than the frequency of the input carrier.

Abstract: A demodulator for demodulating a QAM signal which is usable in combination with an adaptive transversal equalizer. Controls over the demodulator and the equalizer are each converged to an optimum point so that the sampling points of two analog-to-digital converters of the demodulator are optimally controlled. For a limited occupied bandwidth of a carrier passband, a large amount of data may be transmitted with distortions due to delay and attenuation inherent in a transmission path compensated for.

Abstract: An FM signal demodulator has a phase shifter including transversal filters for producing from a FM video signal two FM video signals which are different in phase by 90.degree. from each other, and a demodulator for detecting phase information of the FM video signal, wherein the carrier frequency is at least quadrupled prior to demodulation so as to suppress components of the FM video signal not to be included in the demodulated video signal.

Abstract: An FET oscillator wherein a bias circuit is connected to a drain of a field-effect transistor and a source circuit including a transmission line and a self-bias circuit is connected to a source of the transistor, so that the source is substantially open-circuited at an oscillation frequency and the field-effect transistor operates as a two-terminal (the gate and drain) element exhibiting a negative resistance, and wherein a resonant circuit is connected to the gate of the transistor. With the source circuit connected to the transistor source, the oscillator can have a high unloaded Q-value of Qo and a high externally-loaded Q-value of Q.sub.ext, whereby the oscillation frequency is stable. According to this oscillator, only a single bias circuit for the drain is required without the need of a bias circuit for the gate.

Abstract: In the conversion of a first delta modulated signal with a first bit rate into a second delta modulated signal with a second bit rate, a first and second digital signal derived respectively from the first and second delta modulated signals are compared together in an adding circuit (58) followed by an integration circuit (55). In this way an analog intermediary signal can be avoided and the circuit complexity is small.

Abstract: A push-pull current-fed parallel resonant oscillator includes a parallel resonant LC tank circuit with one end coupled to one terminal of a DC current source via a serially connected first diode and first switching transistor and the other end of the tank circuit coupled to said one terminal via a serially connected second diode and second switching transistor. Respective capacitors (17, 21) shunt the series connections. The tank circuit inductor includes the primary of a transformer whose secondary is part of the transistor drive circuit. The circuit parameters are chosen to provide a duty cycle less than 50% and a high voltage gain of the AC tank voltage. The transistors are controlled to delay the turn-off time of the on-transistor thereby allowing a negative voltage to develop on the opposite capacitor which in turn delays turn-off of its parallel connected transistor so as to provide a dead-time (.DELTA.t.sub.2) during the switching interval in which both transistors are simultaneously off.

Abstract: An inductorless quadrature demodulator for frequency modulated signals is disclosed. A limited FM signal is passed through an active filter (26) and a phase shift network (30) to produce a quadrature signal. The limited FM signal is compared with the quadrature signal in an EXCLUSIVE OR gate (24) and then low pass filtered (36) to obtain recovered audio. The active filter (26) includes a transconductance amplifier (60) whose center frequency can be adjusted by appropriate adjustment of the amplifier's bias current. The bias current is temperature compensated to allow operation of the demodulator over a wide temperature range.

Abstract: Microwave dielectric resonator apparatus which, for example, may be a microwave oscillator frequency stabilized by a dielectric resonator or may be a microwave filter whose critical frequency is determined by a dielectric resonator, has the dielectric resonator environmentally protected in a hermetic chamber. As the hermetic integrity of the chamber would be destroyed by having a tuning slug therein at the end of a screw threaded into a tapped hole through a chamber wall for rotation by a screwdriver outside the chamber, the tuning slug is instead located within a non-hermetic chamber at the end of a screw threaded into a tapped hole through a wall of the non-hermetic chamber serving also as an outer wall of a housing enclosing both chambers. The chambers have an interface which is transparent to microwave fields and proximate the dielectric resonator and tuning slug.

Abstract: Device for correcting deviations upon focussing a laser beam, which comprises electronic means, among which a quadrant detector, for forming with the output signals of said quadrant detector a correction signal -K.sub.1 V.sub.c H.sub.c /.SIGMA. (18), which is added (19) to the focussing signal (A+C)-(B+D) formed in circuit 14, A, B, C and D being the output signals of the quadrant detector (9a, 9b, 9c, 9d),V.sub.c =(A+B)-(C+D)formed in circuit 15;H.sub.c =(A+D)-(B+C)formed in circuit 17;.SIGMA.=A+B+C+Dformed in circuit 16 and K.sub.1 being a constant.

Abstract: A voltage controlled oscillator (VCO) is described which comprises a plurality of inverter stages of odd number connected in a ring with the output of each stage connected to the input of the next stage via a voltage controlled impedance provided by the transconductance of pass transistors. In one embodiment, this VCO is incorporated into a Phase-Lock Loop circuit, in which the gates of the pass transistors are connected to a control circuit which provides a variable biasing voltage to the gates inresponse to speed-up or slow-down signals provided by a phase detector. The bias on the gates adjusts the frequency of the voltage controlled oscillator, in accordance with the speed-up or slow-down signal. The phase detector is coupled to a stream of input data pulses and to a reference train of clock pulses provided by the voltage controlled oscillator.

Abstract: A tuned oscillator is disclosed which comprises an active element, a resonator electrically connected to the active element and made of a magnetic material using ferro-magnetic resonance phenomenon, and a magnetic circuit for applying a magnetic field to the resonator. The resonator is made of an YIG (yttrium, iron and garnet) thin film magnetic resonance element formed by a thin film forming technique and utilizes an uniform mode ferro-magnetic resonance in the YIG thin film, and operating under the application of magnetic field of the magnetic circuit.

Abstract: A holographic method for determining rotational effects upon either gear of gears (1, 2) of a gear set having respective mutually orthogonal rotational axis (C.sub.1, C.sub.2). Particularly, a holographic recording medium or element 12 is secured to gear (1) so that is rotates in synchronization therewith about axis (C.sub.1). Gear (2) is illuminated by a pulsed collimated light beam (L) emitted from a source (14) such as a laser. Beam (L) is reflected from gear (2) as object beam (0) substantially parallel to axis C.sub.2 and means such as a semi-reflective mirror 16 having a slit (18) is provided for directing a reference beam (R) and object beam (0) towards element (12). Development of element (12) after exposing it to beams (R and 0) at two different rotational conditions provides interference lines (f.sub.1, f.sub.2) enabling a viewer of the holographic image of gear 2 to determine the effect of rotation thereupon.

Abstract: A voltage controlled oscillator (VCO) for a television tuner for tuning a large number of television channels, including signals in the microwave frequency range, the VCO comprising a printed circuit (PC) board having a dielectric substrate, a patterned metal layer on one side of the substrate, and a substantially continuous metal layer forming a ground plane on the other side of the substrate, a transistor mounted on the ground plane side of the PC board, and having emitter, base and collector leads projecting laterally from the transistor, the base of the transistor being connected to the ground plane, a d-c supply circuit connected to the transistor, a tuned circuit connected across the collector and emitter of the transistor, the tuned circuit including at least one ground connection to the ground plane of the PC board, the d-c supply circuit, the tuned circuit, and the transistor having values which produce an oscillating output at a frequency of at least one GHz, and the ground connections being interco

Abstract: A spectral analyzer and direction indicator system (10) is disclosed and includes first and second optical channels (20,30) for providing detected optical information indicative of incidence direction and spectral content of incident radiation. The first optical channel includes a reflector element (11) having a non-ruled section (11a) and a spectrally dispersing ruled section (11b); an analytical optical system (13); and a detector array (15). In the reflector element of the first optical channel the non-ruled section is tilted relative to the ruled section. The second optical channel includes a non-dispersing reflector element (17), an analytical optical system (19), and a detector array (21).