Abstract: A multi-tap RF modulator includes an amplifier for amplifying a telecast RF signal input to an antenna input port; a modulation section for modulating the RF signal output from a VCR, SVR, or game player; and a mixer/splitter having more than one RF output tap and for mixing the first RF signal output from the amplifier and the second RF signal output from the modulation section, the mixed RF signals being distributed into more than one RF signal. The modulator with more than one output tap enables a user to view several TV sets at the same time.

Abstract: In a receiver, a tunable parallel resonant circuit (PRC2) is coupled to an input (IN) of a transistor circuit (MOIC) via a coupling network (CNW). The coupling network (CNW) lacks a varicap diode but includes a coupling resistor (Rc) in series with a coupling capacitor (Cc).

Abstract: An article comprising a micro-machined filter advantageously comprises a micro-machined resonator, a drive circuit and a detection circuit, at least a portion of which are circuits are disposed on the resonator within a magnetic field. In operation, an input signal is delivered to the drive circuit. The resonator is excited to movement by the Lorentz force that is generated as signal current varies. Due to the resonator's movement, a voltage is induced in the detection circuit, which moves with the resonator. Using well-known micro-machining techniques, a resonator can be made that has mechanical resonance frequencies extending into the GHz regime. Under proper conditions, such resonances advantageously exhibit very high Q-values, so that the resonator shows a significant physical response (e.g., movement) over a very narrow range of excitation frequency. When the frequency of the input signal matches such a frequency (i.e., the resonant frequency), the device generates a voltage having such a frequency.

Abstract: A radio receiver with isolation between an antenna and a regenerative oscillator/detector. The isolation is provided by periodically (at the receiver's quench frequency) uncoupling the antenna from the regenerative oscillator/detector. The receiver preferably includes an antenna, a super-regenerative oscillator/detector, a clock that indicates the quench frequency, a timing circuit coupled to the clock, and a switch coupled to the antenna, to the oscillator/detector, and to the timing circuit. The timing circuit specifies a first part and a second part of each clock period. During the first part of each clock period, the switch at least partially couples the antenna to the oscillator/detector on the nominal reception frequency. During the second part of each clock period, the switch at least partially uncouples these two elements on the nominal reception frequency.

Abstract: In an FDNR type active filter fabricated on an integrated circuit, an FDNR circuit is provided wherein one ends of a first capacitor and an impedance element are connected to an inverted input of an operational amplifier, one ends of the impedance element and a second capacitor are connected to an output end of the operational amplifier, and the other ends of the first and second capacitors are connected to each other. To the impedance element, resistors are connected in series. To the connecting end of the resistors, one end of another resistor is connected, the other end thereof being grounded in an alternating current form. The capacity value of the second capacitor is greater than that of the first capacitor.

Abstract: A high-frequency composite component used for a multi-band system, includes first and second circuits connected in parallel, the first and second circuits having infinite input impedances respectively at first and second frequencies, corresponding to first and second bands. Each of the first and second circuits includes a phase shifter, and a trap circuit connected as a load of the phase shifter. The phase shifter of each of the first and second circuits includes a strip line having a length of .lambda./4, wherein .lambda. is a wavelength corresponding to one of the first and second frequencies. The trap circuit of each of the first and second circuits includes a series resonance circuit, and the trap circuit resonates at one of the first and second frequencies.

Abstract: A radio receiving apparatus includes a high-frequency amplifier, an intermediate-frequency amplifier, a reception electric field strength detector, and a control section. The high-frequency amplifier is connected to a signal line of a reception system for a radio signal and can be disconnected from the signal line. The intermediate-frequency amplifier is connected to the signal line on an output side of the first circuit element and can be disconnected from the signal line. The reception electric field strength detector detects the reception electric field level of a radio signal. The control section performs control to disconnect at least one of the first and second circuit elements from the signal line and also performs control to stop supplying power to the disconnected circuit element in accordance with the electric field level detected by the reception electric field strength detector.

Abstract: A micro-receiver for receiving a high frequency frequency modulated or phase modulated signal, including a single integrated circuit in BiCMOS technology and on which is integrated a high frequency amplifier, an oscillator, a modulator, an intermediate frequency filter, an intermediate frequency amplifier, a demodulator, a low pass filter and a low frequency amplifier. The integrated circuit includes in addition a muting or squelch circuit, a voltage multiplier as well as a standby circuit. The circuits working in a lower frequency range are implemented in CMOS technology, and operated in a very energy-saving way with a single-cell battery with a low battery voltage of 1.3 V. The voltage multiplier provides a higher operating voltage for the circuits working in a higher frequency range.

Abstract: A detector circuit (100) for detecting signaling information transmitted with a radio frequency (RF) signal for interpretation by a radio receiver includes a first low pass filter (105) for filtering demodulated audio signals that are directly coupled thereto and for providing a first filtered signal. A second low pass filter (109) is directly coupled with the first low pass filter (105) for filtering the first filtered signal and providing a second filtered signal. A signaling detector (111) is then directly coupled with the second low pass filter (109) for determining the frequency and/or bit code of signaling information included in the second filtered signal.

Abstract: A radio frequency apparatus has a tuner unit which is disposed in a tuner unit housing, and a demodulation unit which is disposed in a demodulation unit housing easily attached or removed to the tuner unit housing by a connecting device provided on side walls of the tuner unit housing and the demodulation unit housing.

Abstract: A radio transceiver including a counter for outputting a DC compensation signal, an amplifier for receiving a input signal having a DC component and for receiving the DC compensation signal and forming a signal difference between the input signal and the DC compensation signal and a comparator for comparing the signal difference and a reference signal. The counter increases and decreases the DC compensation signal based on the output of the comparator such that the incrementation or decrementation of the counter is based on the DC component of the signal difference.

Abstract: There is provided a tuner capable of improving reliability thereof with reduced power consumption and reduced heat generation. In the tuner, one wideband amplifier circuit including one transistor constitutes a buffer amplifier. The wideband amplifier circuit is coupled with a first local oscillator circuit in a DC coupling style. With the above-mentioned arrangement, the buffer amplifier is allowed to have a simplified circuit construction and reduce noises. Since the amplifier circuit and the local oscillator circuit are coupled with each other in a DC coupling style, reduced power consumption can be achieved.

Abstract: An RF antenna and an associated receiver are proximately located in an integrated antenna/receiver unit thereby eliminating the need for baluns and inter-component cabling characteristic of prior designs. Integration of the receiver with the antenna provides for improved sensitivity as the need for utilizing signal dissipating and noise introducing cables and baluns to transmit the signal received by the antenna to the receiver is eliminated. Direct coupling of the antenna and receiver on a single gallium arsenide integrated circuit maintains balanced impedance from the antenna to the receiver.

Abstract: The hub station of a network receives a multiplicity of signals in different frequency channels and possibly on different antennas. The individual signals to be demodulated may coexist in a radio frequency channel using FDMA, TDMA, or CDMA or other signal types or combinations thereof. The received frequency band is divided into subbands which are all translated to baseband and distributed to the backplane of one or more demodulator chassis (each of which contains many demodulators). In this way, any demodulator may be connected to any signal. Relatively large segments of the input bandwidth are translated to baseband. These segments are then digitized and further band segmentation is performed digitally. In this way, the digitation and switching functions are almost all done with digital hardware. This affords considerable advantage in hardware cost, size, and reliability.

Abstract: A television receiver powered by an alternating current power source includes an electrically conductive chassis coupled to one side of the AC source, a radio frequency tuner coupled to the chassis, and a coaxial cable having an inner conductor and an outer shielding conductor for supplying filtered radio frequency signals to the tuner. The outer conductor is comprised of an electrically conductive housing circumposing the inner conductor for at least a portion of its longitudinal length, and providing electrical connection and mechanical support for the cable assembly. Filtering of the signal is provided by one or more ferrite beads disposed about the outer conductor, and capristor/capacitor devices.

Abstract: A satellite broadcasting tuner with which satellite broadcasting of any channel can be enjoyed only by a channel selecting operation thereof whether or not broadcasting of the channel involves special signal processing.

Abstract: The present disclosure includes a discussion of a radio receiver. The radio receiver has at least two operational states and includes a variable gain amplifier and at least two adaptive DC offset compensators (421, 427) to suppress undesired DC offset. The first operational state of the radio receiver (121) adjusts the adaptive DC offset compensator circuits (421, 427) to appropriate output levels in absence of an input signal to the radio (121). The second operational state receives the input signal through the radio receiver (121) and eliminates the undesired DC offset (309) from the received input signal with the adaptive DC offset compensator circuits (421, 427) and allows the received input signals to be processed.

Abstract: A down converter device is disclosed which is used in a satellite communication system to convert a microwave signal to an intermediate frequency signal by the use of a standard signal having a frequency range of several to several tens of MHz, and to apply the intermediate frequency signal to a next stage component. The down converter includes a mixer for producing the intermediate frequency signal indicative of a frequency difference between the standard signal and the microwave signal. A separator is provided which includes a first terminal for receiving the intermediate frequency signal, a second terminal for producing and supplying the intermediate frequency signal to the next stage component and for receiving the standard signal from the next stage component, a first filter for separating the standard signal, and a third terminal for producing the standard signal to the mixing means.

Abstract: A television (TV) receiving system includes a first TV receiver for receiving TV signals in a first range of frequencies, such as are used for cable, VHF and UHF broadcasting including a frequency synthesizer type local oscillator. The frequency synthesizer uses a voltage controlled oscillator (VCO) controlled by a tuning voltage responsive to a first frequency feedback signal. The receiver includes a coupling arrangement for adapting the receiving system for use with an external plug-in unit including a second TV receiver for receiving TV signals in a second range of frequencies, such as are used for direct broadcast satellite (DBS) signals. The second TV receiver provides a second frequency feedback signal. The receiving system includes a multiplexer for selectively coupling one of the first and second frequency feedback signals to the frequency synthesizer for controlling the VCO.

Abstract: In a UHF tuner having a diode mixer and a double-tuned circuit; a UHF tuner of good tuning characteristics comprising the fact that a .pi.-type impedance converter portion consisting of capacitors is disposed in a coupling part between the diode mixer and the double-tuned circuit.

Abstract: The output of a doubly-balanced mixer of a television tuner is terminated by a network which exhibits the characteristic impedance of the mixer for both the sum and difference frequency components. The difference frequency component termination simply consists of an inductor and a capacitor connected as a series-tuned circuit and a resistive element connected in series between the output of the mixer and signal ground. The inductor and capacitor are selected resonate at a frequency in the passband of the IF section and the resistive element is selected to exhibit the characteristic impedance of the mixer. The sum frequency component termination simply consists of a capacitor and a resistive element connected in series between the output of the mixer and signal ground. The capacitor is selected to exhibit negligible impedance just below the lowest frequency of the sum frequency component and the resistive element is selected to exhibit the characteristic impedance of the mixer.

Abstract: An RF receiver having a coupling capacitor connected between the back end of the receiver and the input to a data limiter circuit, a battery saver strobe feature which periodically turns the receiver ON and OFF and a precharge circuit for precharging the coupling capacitor. The receiver further includes a reference voltage stabilization circuit which prevents a received signal from reaching the output of the back end of the receiver during the precharging of the coupling capacitor in order to minimize the voltage offsets from the desired unmodulated carrier frequency reference voltage which results in erroneous data being decoded by the decoder portion of the RF receiver.

Abstract: In a portable radio receiver of the type wherein a metal member forming a loop antenna surrounds the circuit components making up the receiver circuitry, the receiver is provided with high impedance elements in series with at least the power supply and grounding lines at some point between the power supply and the RF-IF converter. The antenna circuitry may also include a high impedance element in series with the signal path at some point downstream of the RF-IF converter.

Abstract: A selection circuit for series connection between the output of the detector stage and the input of the audio amplifier. The selection circuit requires a minimum number of components and is useful to drive a tuning indicator or similar type circuit.

Abstract: 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 ferrite core, while the second of these coils connects the same input of the mixer stage to the output of a local oscillator in such a way that two signal paths leading towards the mixer stage, respectively for the high-frequency signal and the oscillator signal, go through coupled coils in opposite winding directions. The result is that the path for signals in either direction between the local oscillator and the input stage are of much higher impedance than the paths for signals proceeding to the mixer stage respectively from the input stage and from the local oscillator.