Patents Examined by John Kominski
  • Patent number: 3949324
    Abstract: A system for generating angular modulation comprising a balanced modulator and an adding circuit to which a surface wave device quadrature oscillator applies two signals at the carrier frequency differing 90.degree. in phase, such phase difference being accurately maintained independent of aging and variations in operating temperatures. More particularly, an information signal is applied to one input of the balanced modulator, the output of which is applied to the adding circuit. The surface wave device oscillator completes the system by applying an in-phase carrier frequency to a second input of the balanced modulator and a carrier frequency shifted 90.degree. in phase to a second input of the adding circuit. Angular modulation is thus produced at the output of the adding circuit.
    Type: Grant
    Filed: November 11, 1974
    Date of Patent: April 6, 1976
    Assignee: Texas Instruments Incorporated
    Inventors: Benjamin L. Lowe, Jerry D. Holmes
  • Patent number: 3946330
    Abstract: A voltage controlled oscillator circuit comprises a voltage controlled oscillator circuit, first and second constant-current circuits respectively for causing first and second constant currents, current dividing means for dividing the first constant current in accordance with an outside control voltage, and means for adjustably varying the control voltage. The oscillation frequency is controlled responsive to an input control current equal to the sum of one of the divided currents and the second constant current. The adjustment means causes an adjustment of the output currents of the current dividing means and of the free-running oscillation frequency.
    Type: Grant
    Filed: March 25, 1975
    Date of Patent: March 23, 1976
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Nobuaki Takahashi
  • Patent number: 3946271
    Abstract: A strobe lamp power supply control circuit for use with a high intensity strobe lamp operating at a high flashing rate in parallel with a capacitor storage arrangement is disclosed. Strobe lamp after-glow is quickly eliminated after each flash. This is accomplished by providing an SCR which disconnects the power source from the capacitor storage arrangement and the strobe lamp for a sufficient time to allow the after-glow to dissipate. A zero crossing detector is provided to protect the SCR from surge currents by permitting the SCR to be gated on only when there is a zero potential across the terminals of the SCR. Additionally, the capacitor storage arrangement may be used to supply either of two strobe lamps when a voltage limiting circuit is activated to regulate the amount of energy stored.
    Type: Grant
    Filed: December 26, 1974
    Date of Patent: March 23, 1976
    Assignee: Grimes Manufacturing Company
    Inventors: Gregory Stepp, Michael Dennis Patrick, Sr.
  • Patent number: 3944940
    Abstract: A clock pulse generating system is disclosed for recovery of read data from magnetic record media comprised of a phase-locked loop for tracking data pulses. The loop employs simple digital logic gates for phase error detection, third-order filtering for the transient phase and frequency error reduction and a voltage controlled oscillator (VCO) comprised of a capacitor charged by current from a voltage controlled current source, voltage threshold detection means, and means responsive to the threshold detection means to quickly discharge the capacitor. The VCO includes a flip-flop at its output to produce a square-wave feedback signal to the phase detection gates and to a data recovery circuit.
    Type: Grant
    Filed: September 6, 1974
    Date of Patent: March 16, 1976
    Assignee: Pertec Corporation
    Inventor: Ashok K. Desai
  • Patent number: 3944949
    Abstract: A frequency modulator includes a capacitor, a controlled current source, and a bistable circuit. The current source and bistable circuit operate to alternately vary the charge in opposite directions on the capacitor. The frequency of opposite charge variation is controlled by the amplitude of the input signal applied to the current source. A control circuit coupled to the capacitor and the bistable circuit varies the frequency of opposite charge variation to provide a linear frequency versus input signal amplitude.
    Type: Grant
    Filed: November 18, 1974
    Date of Patent: March 16, 1976
    Assignee: Ampex Corporation
    Inventor: William Frederic Herzog
  • Patent number: 3944877
    Abstract: A wireless multiflashlight apparatus simultaneously illuminates a subject by flashlight rays emitted from a main flashlight device mounted on a photographic camera and at least one additional flashlight device located at suitable position away from the main flashlight device. In the main flashlight device is provided a flash tube arranged to emit substantially two or more flashlight rays at a predetermined time interval therebetween upon the shutter operation of an associated camera. In the additional flashlight device are provided a decoder for producing an outlet signal only upon receipt of the flashlight rays from the main flashlight device through a photo-electric conversion element and an amplifier, and a flash tube operative to be triggered only by the output signal from the decoder. The additional flashlight device is protected from inadvertently flashing even upon reception of any flashlight rays from other flashlight devices than the associated main flashlight device.
    Type: Grant
    Filed: June 13, 1974
    Date of Patent: March 16, 1976
    Assignee: Satoh Cohki Co., Ltd.
    Inventor: Fukuji Sato
  • Patent number: 3944946
    Abstract: The generation of controlled, electromagnetic, coherent, microwave radiation from a warm, uniform plasma at approximately twice the plasma frequency by means of a source of high energy electrons being directed into a plasma and coupling the resultant energy from a cavity resonator to external circuitry.
    Type: Grant
    Filed: November 15, 1974
    Date of Patent: March 16, 1976
    Inventors: Balram Prasad, Clare C. Leiby, Jr.
  • Patent number: 3944939
    Abstract: Demodulator assembly for m data trains, with differential phase modulation, comprising, for each train, an elementary demodulator dimensioned over a space of one bit, whereas the coding is effected over a space of n intermediate bits, comprising, for each train, a shift register having n+1 flip-flops in a functional connection with an adder.
    Type: Grant
    Filed: April 16, 1974
    Date of Patent: March 16, 1976
    Assignee: Societe Lannionnaise d'Electronique Sle-Citerel
    Inventor: Bernard Le Mouel
  • Patent number: 3943463
    Abstract: Disclosed is microwave oscillator or amplifier circuitry which is tunable over a wide bandwidth and which includes an improved variable loading on a negative resistance semiconductor diode, such as an IMPATT diode. This loading is provided in mutually perpendicular directions closely adjacent the diode. In one direction, a DC bias connection is mounted together with an adjustable coaxial filter thereon, and this filter serves as a series tuning element for the diode. A movable short is mounted for adjustment in a direction perpendicular to that of the above coaxial filter and provides parallel tuning for the diode. These series and parallel tuning elements are operative to match the real and imaginary components of the diode impedance to the real and imaginary components of the load impedance, respectively, at a particular operating frequency, thereby maximizing the power transfer and the DC to RF conversion efficiency of the circuitry.
    Type: Grant
    Filed: January 20, 1975
    Date of Patent: March 9, 1976
    Assignee: Hughes Aircraft Company
    Inventors: Hiromu J. Kuno, David L. English
  • Patent number: 3943460
    Abstract: A frequency conversion system for converting high to low frequencies. The system comprises a first frequency dividing means for frequency dividing the frequency of an input signal into 1/MN of the same, a voltage controlled oscillator, a second frequency dividing means for frequency dividing the output frequency of the voltage controlled oscillator into 1/(N + 1) of the same, a phase detector for controlling the voltage controlled oscillator such that the frequencies of the respective outputs of the first and second frequency dividing means are equal to one another, and means for sampling the input signal by using the output frequency of the voltage controlled oscillator to lower the frequency of the input signal to 1/N thereof.
    Type: Grant
    Filed: September 20, 1974
    Date of Patent: March 9, 1976
    Assignee: Iwatsu Electric Co., Ltd.
    Inventor: Minoru Arai
  • Patent number: 3943459
    Abstract: A variable frequency voltage controlled oscillator is tuned to a selected frequency by applying a varying voltage to the control port of the oscillator to sweep the oscillator signal through a frequency range which includes the frequency of a reference frequency source. The value of the varying voltage is stored at the instant the oscillator frequency coincides with the frequency of the reference source. A dc offset voltage is then added to the stored voltage to produce a sum voltage which is substituted for the varying voltage at the control port of the oscillator to tune the oscillator to the selected frequency. The offset voltage is equal to the difference in the control voltages at the selected and reference frequencies and may be determined from the oscillator control voltage characteristic.
    Type: Grant
    Filed: April 2, 1975
    Date of Patent: March 9, 1976
    Assignee: Cutler-Hammer, Inc.
    Inventor: Paul S. Tosto
  • Patent number: 3943379
    Abstract: Logic circuit for dividing an input frequency symmetrically by an odd number without producing spurious transients.
    Type: Grant
    Filed: October 29, 1974
    Date of Patent: March 9, 1976
    Assignee: RCA Corporation
    Inventor: William George McGuffin
  • Patent number: 3942059
    Abstract: An X-ray tube with a rotating, motor-driven anode made up from a disc of graphite covered on a major portion of its convex surface which is turned away from its axis of rotation by a layer of an X-ray emissive refractory metal or alloy which has a much lower coefficient of thermal emissivity than the other face of graphite. To reduce thermal radiation in the direction of the rotor to which the anode is secured, the X-ray emissive, convex, covered surface of the anode, which is subjected to electron bombardment, is turned toward the rotor and the cathode lies on the same side of the anode as the rotor of the driving motor, resulting in reduced operational temperatures of these parts. Additional thermal protection for the rotor and bearing is afforded by providing a reflective surface on the rotor or by installing a protective disc-shaped shield between the rotor and the anode. The reduced temperatures of rotor and bearing permit increased output power and lengthened operating periods of the X-ray tube.
    Type: Grant
    Filed: June 12, 1974
    Date of Patent: March 2, 1976
    Assignee: Compagnie Generale de Radiologie
    Inventor: Dang Tran-Quang
  • Patent number: 3942069
    Abstract: A discharge lamp lighting apparatus includes three oscillation circuits. The first comprises a linear inductor and a capacitor connected in series to a power source. The second oscillation circuit is connected across the capacitor and includes a bounce or backswing booster inductor and a voltage responsive switching element connected in series. The third oscillation circuit comprises the bounce inductor and its distributed capacity. The bounce booster inductor has a magnetic core with a shape and of a material providing an abrupt saturation characteristic. The core factor K of the core is small and may have a ratio of the cross sections of the wound to the unwound parts thereof of less than one half. Alternatively, the ratio of the wound part of the core to the unwound part thereof is less than one fourth and a conventional core material may be employed for the core.
    Type: Grant
    Filed: September 9, 1974
    Date of Patent: March 2, 1976
    Assignee: NEC Sylvania Corporation
    Inventor: Isao Kaneda
  • Patent number: 3942134
    Abstract: The base of a first transistor is coupled through a first capacitor to the collector of a second transistor and the base of the latter is coupled through a second capacitor to the collector of the first transistor. The capacitors are alternately charged by means of first and second relatively constant current sources connected to the collectors of the first and second transistors, respectively. The charging current supplied by the first current source to the second capacitor flows into the base of the second transistor, causing it to saturate and conduct the current supplied by the second current source. The charging current supplied by the second current source to the first capacitor flows into the base of the first transistor, causing it to saturate and conduct the current supplied by the first current source.
    Type: Grant
    Filed: December 3, 1974
    Date of Patent: March 2, 1976
    Assignee: RCA Corporation
    Inventor: Otto Heinrich Schade, Jr.
  • Patent number: 3942066
    Abstract: In a velocity modulation tube comprising a floating prebuncher and at least one final prebuncher, frequencies of respective fundamental modes of resonance of the input cavity, the floating prebuncher, and the final buncher are adjusted to the lowest frequency of the passband of the tube, adjacent to the highest frequency of the passband, and higher than the highest frequency, respectively. Furthermore, the Q-value of the floating prebuncher is made equal to or lower than that of the input cavity. Naturally, the output cavity has its fundamental mode of resonance approximately at the center of the passband.
    Type: Grant
    Filed: February 24, 1975
    Date of Patent: March 2, 1976
    Assignee: Nippon Electric Company Limited
    Inventors: Takao Kageyama, Yosihiro Morizumi
  • Patent number: 3940693
    Abstract: A phase detector which utilizes an amplifier that has the input signal coed by resistive elements to both its non-inverting and inverting input terminals operates with an amount of negative feedback determined by the magnitude of the resistive element associated with the inverting input terminal. The reference signal controls a switching device which grounds the non-inverting terminal during the time when this signal has a particular polarity. As a consequence, the gain of the amplifier shifts between equal, positive and negative values in synchronism with changes in the polarity of the reference signal, and the average value of the output signal of the amplifier is indicative of the phase relationship between the input and reference signals when these signals have the same frequency.
    Type: Grant
    Filed: October 24, 1974
    Date of Patent: February 24, 1976
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Neil L. Brown
  • Patent number: 3939438
    Abstract: In a phase locked oscillator (PLO), the frequency of a voltage controlled oscillator (VCO) is changed in response to error signals indicating the phase error between the individual pulses of a stream of input pulses and the output pulses of the PLO. The running of the PLO is temporarily interrupted whenever the phase error exceeds a predetermined amount, and is restarted in phase with the next input pulse from the stream of pulses. A residual part of the error signal causing the interruption is accumulated so that after each interruption the frequency of the oscillator is closer to the frequency of the input stream of pulses. The process is repeated as required until phase lock is achieved.
    Type: Grant
    Filed: January 23, 1975
    Date of Patent: February 17, 1976
    Assignee: International Business Machines Corporation
    Inventor: John Richard Taylor
  • Patent number: 3939411
    Abstract: An improved instantaneous frequency measurement system which can measure se signals of differing frequencies emitted simultaneously by a single source. A conventional instantaneous frequency measurement detector is preceded by a gating device and a dispersive delay line which cooperate to transform the simultaneous signals into time sequential signals.
    Type: Grant
    Filed: October 3, 1974
    Date of Patent: February 17, 1976
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Wilbur G. James
  • Patent number: 3938040
    Abstract: The present invention relates to an apparatus for measuring the level of a signal voltage supplied to the control input of a controllable constant current source whose output is connected to a phase inverting circuit conducting in one direction and to a rectifier conducting in the opposite direction so that a full-wave rectified current is obtained which is adapted to flow through a measurement device in order to obtain a measure of the voltage level.
    Type: Grant
    Filed: March 22, 1974
    Date of Patent: February 10, 1976
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventor: Bengt Gustav Lofmark