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| Number | Title | Issue Date |
| 4369519 | Cross polarization compensation system A cross polarization compensation system, in which an input elliptically polarized wave is converted, by a first rotatable differential phase shifter having a phase shift of 90° or less than 90°, into an elliptically polarized wave defined by (where &#x... | 01/18/1983 |
| 4340972 | Transmitter/receiver teaching apparatus A teaching apparatus including a transmitter portion, a receiver portion and a prompter portion, each of the portions being disposed in a separate self-contained unit, the transmitter portion being adapted to be worn on the head and including a peripheral... | 07/20/1982 |
| 4326295 | Television tuner circuit A television tuner comprises a VHF tuner section and a UHF tuner section and is configured in the two tuned modes of VHF high band and VHF low band between which the input tuning circuit of the VHF tuner section is switched by a diode in response to a sou... | 04/20/1982 |
| 4325142 | Portable radio set with a carrying holder A switch and an actuator therefore are arranged, respectively, on the portable radio unit and the carrying holder therefore in a manner such that, when the radio unit is inserted in the carrying holder, the switch is actuated to disconnect the microphone-... | 04/13/1982 |
| 4320533 | Frequency stabilized downconverter facilitating output frequency alteration A downconverter having a voltage controlled local oscillator supplied with a control DC voltage, obtained from a frequency discriminator and responding to variations of the difference between a reference produced by a stable oscillator and an output signa... | 03/16/1982 |
| 4320523 | Digital signal reception system The error rate performance of a digital radio system which is deteriorated due to inband interference components can be effectively improved by adopting the present digital signal reception technique. According to the present invention, a narrow band band... | 03/16/1982 |
| 4317215 | Tuning system for CATV terminal In a CATV system, channel identifying data is incorporated in each transmitted channel, and subscriber terminals return such data to the CATV center to indicate the channel actually being received. Further, the channel identifying data is compared to the ... | 02/23/1982 |
| 4317221 | Mobile data receiving system A mobile data receiving system for a mobile communication system is disclosed. A clock signal for a digital phase synchronization loop circuit used for receiving digital data such as a dial number is obtained by multiplying or dividing the frequency of th... | 02/23/1982 |
| 4317224 | Oil-cooled radar transmitter apparatus A radar transmitter apparatus comprising a radar transmitter equipped with a modulator arranged in an oil-filled housing, the modulator being held in spaced relationship with respect to the inner walls of the housing in order to form an intermediate space... | 02/23/1982 |
| 4317220 | Simulcast transmission system A simulcast transmission system is disclosed. The system comprises a master station including means for generating and transmitting over a medium an audio signal containing a message signal and a pilot frequency signal inserted into the audio signal band,... | 02/23/1982 |
| 4315332 | Electronic timepiece radio Disclosed is an electronic timepiece radio having an electronic timepiece circuit, a circuit for detecting a time signal and correcting the time indication of the electronic timepiece by the detected time signal. And a preset system receiving circuit can recei... | 02/09/1982 |
| 4314374 | High power audio frequency transmitter A high power amplitude modulated audio frequency transmitter having a Twin-T low frequency oscillator, a tickler coil high frequency oscillator, a switching regulator and a switching amplifier. The Twin-T low frequency oscillator produces a sine wave modu... | 02/02/1982 |
| 4314378 | Antenna low-noise Q spoiling circuit An input coupling circuit for detuning the Q of a high-Q ferrite rod antenna is disclosed. A high-impedence low-noise amplifier is used to amplify the output signal from the LC resonant tank of the rod antenna. A portion of the amplified signal is fed bac... | 02/02/1982 |
| 4314372 | Methods and means for producing and reproducing transmitted or recorded sound or video signals A sound transmission and reproduction system including at the transmitter side means for producing a non-audible control signal indicative of a predetermined character of the transmitted sound, preferably the intensity of the sound as actually transmitted... | 02/02/1982 |
| 4313197 | Spread spectrum arrangement for (de)multiplexing speech signals and nonspeech signals It is known to multiplex speech signals and nonspeech signals over a common communication path. One arrangement uses a portion of the frequency spectrum of the path for speech signals with the remainder for nonspeech signals. Another inserts data signals ... | 01/26/1982 |
| 4313222 | H-F Portion of TV receiver The output electrode of a field effect transistor of a high-frequency input stage is connected to a capacitively coupled input (gate) electrode of the field effect transistor of a mixer stage through one of a pair of bifilarly wound coils provided on a fe... | 01/26/1982 |
| 4310923 | Two-way transceiver including frequency synthesizer A two-way business-band transceiver for operation on an assigned FCC frequency includes a chassis housing a plurality of printed circuit boards which are surrounded by a three-part enclosure. This enclosure includes a main body portion having a top half a... | 01/12/1982 |
| 4310924 | Channel programming apparatus for a signal receiver A programming apparatus is provided for use with a signal receiver, such as a television or FM broadcast receiver, of the type whose tuning frequency is determined by a tuning control voltage or other tuning control signal, and whose power supply can be s... | 01/12/1982 |
| 4308621 | Radio interference bucker apparatus An apparatus for intercepting radio waves emitted from a relatively local interference radio-wave-emitting source and processing the same so that they may be fed into the antenna terminal of a radio wave receiver for accomplishing substantially interferen... | 12/29/1981 |
| 4307466 | Audio system for drive-in theaters A drive-in theater having an array of predesignated parking spaces and a central audio output device for generating a carrierless audio signal. Interface devices are located at the spaces and connected in parallel to the output device. Each interface devi... | 12/22/1981 |
| 4306312 | Symmetric mixer for millimeter waves and a receiver using such a mixer The invention aims at obtaining an intermediate beat frequency from two millimeter wave frequencies by attenuating as much as possible the amplitude variations of the frequency coming from the local oscillator. The mixer of the invention comprises two modules ... | 12/15/1981 |
| 4305157 | Tuning circuit using a phase-locked loop A tuning apparatus includes an RF amplifier for receiving a video signal corresponding to a selected channel, a voltage controlled oscillator for producing a local oscillation signal, a mixing circuit for converting the received video signal to an interme... | 12/08/1981 |
| 4305153 | Method for measuring microwave electromagnetic fields A microwave signal is transmitted from a transmitting antenna through a transfer medium to an electrically modulated and mechanically spun microwave scatterer. The scatterer may include an electric field responsive antenna, such as a dipole, for measureme... | 12/08/1981 |
| 4305156 | Rotary switch type television tuner A television tuner comprises a rotary switching shaft, switching plates associated with the rotary switching shaft, and an input tuning portion, an interstage tuning portion and a frequency converting portion coupled to the switching plates and adapted fo... | 12/08/1981 |
| 4305159 | Compressive receiver The envelope detector of a compressive receiver is replaced with either a Fourier Transform device or a demodulator such that the output of the dispersive delay line utilized in the receiver is processed to yield the spectrum of the incoming signals and/o... | 12/08/1981 |
| 4305155 | Exterior mounted remote control television channel selector An exterior mounted remote control television channel selector for use with a television receiver having a conventional manual channel selector knob is provided. A receiver mechanism is provided with a motor that is rotated in response to a remote control... | 12/08/1981 |
| 4305154 | Transceiver The transceiver according to the invention is controlled by an automatic alternation device in order to permit transmission solely when voice signals are to be transmitted and when the receiver does not receive such signals. On transmission, the transmitt... | 12/08/1981 |
| 4298989 | Tuning apparatus In tuning apparatus, a sensor senses when a tune indicating signal has been produced by the IF section so as to enable an adjusting circuit to change the tuning condition of the apparatus by a predetermined frequency step and then to disable the adjusting... | 11/03/1981 |
| 4295164 | Circuit for improving picture quality in a television receiver A circuit for improving picture quality in a television receiver adapted to receive video signals, with light picture areas corresponding to a high video signal level bounded by inclined rising and falling edges comprising, circuit elements for producing ... | 10/13/1981 |
| 4295224 | Tuning indicator apparatus for a frequency synthesizer tuner Tuning indicator apparatus is provided for use with a frequency synthesizer tuner of the type having a phase-locked loop including a reference oscillator, a variable frequency oscillator to produce a local oscillating signal, a programmable frequency divi... | 10/13/1981 |
| 4292686 | Tuning system for receiver of pilot-modulated carrier waves A radio receiver, especially one for automotive vehicles, includes a selector switch operable to cut off the audio stage unless the r-f stage is tuned to a carrier modulated by a pilot frequency which triggers a detector therefor into emission of an enabl... | 09/29/1981 |
| 4291414 | Radio receiver operable in station search mode or station select mode A radio receiver comprising a local oscillator, a first counter circuit for computing an algebraic sum of a number corresponding to an oscillating frequency of the local oscillator and a number corresponding to an intermediate frequency, the algebraic sum... | 09/22/1981 |
| 4290142 | Interactive cable television system An interactive cable television system for serving a plurality of user locations in a service area divided into a plurality of service regions, including a central office and a service network having a portion composed of parallel cables arranged in a tre... | 09/15/1981 |
| 4288876 | Demodulator for frequency modulated signals This new demodulator for frequency modulated signals separates the signals into two distinct paths and delays the signals in one of the paths, with reference to those in the other of said paths, by an integral odd multiple of a quarter of one wavelength o... | 09/08/1981 |
| 4287600 | Frequency synthesizer with ROM controlled divider and display A frequency synthesizer is disclosed in which a single read only memory (ROM) is utilized to directly control programmable frequency dividers in a phase locked loop while also directly controlling the excitation of seven segment visual digital display mod... | 09/01/1981 |
| 4283791 | Circuit arrangement with frequency synthesis for the tuning of receiving sets A circuit arrangement for the selection and the tuning of a radio-electric signal in a signal receiving set is described. The main feature of this set, which comprises a controllable local oscillator whose frequency is controlled by a control loop which mainta... | 08/11/1981 |
| 4281347 | Correction circuit for improving the sharpness of contour of video images A correction circuit for improving the contour sharpness or quality of video images in devices wherein the video signals are converted into digital form. An even number of series connected multi-stage shift registers is provided, whose inputs are each con... | 07/28/1981 |
| 4281415 | Digital tuner A variable rate tuner is one in which the rate of change of tuned frequency with respect to tuning shaft rotation varies automatically as a function of the shaft rotation speed. In this tuner the circuitry is completely digital, including a shaft encoder ... | 07/28/1981 |
| 4277845 | Meteor scatter burst communication system The specfication discloses a meteor burst communication system including at least two spaced apart master stations, in association with a plurality of groups of remote stations spaced at locations remote from the master stations, with each group being ass... | 07/07/1981 |
| 4276655 | Integrated circuit planar high frequency mixer The invention is a cross-bar signal mixer suitable for low-cost high-yield mass production. The mixer configuration consists of a balanced planar taper section supported upon a dielectric substrate placed across the carrier and local oscillator wave guide... | 06/30/1981 |
