Abstract: A tunable wideband distribution circuit for transmitting a wireless signal over a transmission line is disclosed. The tunable wideband distribution circuit may include a programmable gain buffer, wherein the gain of the programmable gain buffer is based at least in part on a frequency of the wireless signal. The tunable wideband distribution circuit may also include a tuning element configured to modify an effective impedance of the transmission line based at least on the frequency of the wireless signal, wherein the tuning element is electrically coupled to the transmission line.

Abstract: A mobile computing device and corresponding method are disclosed. The mobile computing device includes an RF MEMS switch circuit including at least one normally open RU MEMS switch and a normally closed RU MEMS switch and a controller connected to the RU MEMS switch circuit. The RU MEMS switch circuit applies a default condition to the mobile computing device through the normally closed RU MEMS switch, and the controller causes application of control signals to one of the at least one normally open RU MEMS switches and to the normally closed RU MEMS switch to apply an alternate condition to the mobile computing device instead of the default condition.

Abstract: A Radio Frequency (RF) circuit includes an active portion and a tuned portion. The active portion receives an RF signal and that operates upon the RF signal. The tuned portion couples to the active portion and includes a first inductor, a second inductor, and an NMOS transistor. The NMOS transistor has a gate, a drain, a source, and a body. The drain and source operably couple/decouple the second inductor to/from the first inductor. The drain and source are biased at respective operating voltages (greater than ground and less than a first voltage supply) by the active portion and the tuning portion. The body couples to a first voltage supply, via a control circuit or switch in some cases. Applying a second voltage supply (that is greater than the first voltage supply) to the gate turns ON the NMOS transistor.

Abstract: An integrated tuner circuit includes a first terminal to which a UHF TV signal is input via a UHF amplifier. The amplifier is switched to an operating state when a UHF TV signal is received. A switching-voltage generation circuit includes a first switching circuit for generating a switching voltage used to switch the operating state of a UHF high-frequency amplifying circuit.

Abstract: Needless signal that causes interference is prevented from entering to eliminate the generation of interfering signal. A television tuner is provided with a band switching circuit to which television signals of a plurality of channels arranged in a predetermined frequency band are supplied, the band switching circuit has a plurality of filters having the cutoff frequency of every one octave frequency in the predetermined frequency band, the cutoff frequency of the plurality of filters is made continuous every one octave in the predetermined frequency band, and the television signal of the channel to be received is sent out through a specified filter having the cutoff frequency within one octave from the frequency of the television signal of the channel to be received.

Abstract: A double-tuned circuit of a tuner that can be switched for tuning to a plurality of frequency bands by turning a switching diode ON or OFF restrains degradation of a selectivity caused by an undesirable additional tuning circuit or parasitic tuning circuit formed by a capacitance generated when the switching diode is OFF and inter-terminal capacitance of a resistor. A double-tuned circuit of a tuner is also provided that exhibits good selectivity with reduced damping to a tuning circuit in a low-band receiving mode, and also exhibits a wider tuning range. A feed resistor for high-band receiving is directly connected to a switching diode in a primary tuning circuit, and the feed resistor for high-band receiving is connected to a switching diode via a coil in a secondary tuning circuit.

Abstract: A variable frequency oscillator (VFO) circuit having an increased frequency tuning range to selectively obtain operating frequencies above and below a set frequency. The circuit includes a tank inductor connected in parallel with a tank capacitor for primarily defining the set oscillating frequency of the VFO circuit. A switchable capacitor is included for selectively providing a predetermined step-wise decrease of the oscillating frequency to a frequency value below the set frequency of the circuit, and a varactor is included for accommodating selective tuning of the oscillating frequency within a range of frequency values below the set frequency. The inventive circuit selectively includes a switchable inductance element which is selectively electromagnetically coupled to the tank inductor to decrease the overall inductance value of the VFO circuit and, thereby, selectively increase the oscillating frequency above the set frequency value.

Abstract: A receiver for receiving both first-type reception signals, for example TV signals, and second-type reception signals, for example, FM-radio signals. The receiver may be used in multimedia applications. In the receiver, a reception signal is fed via an input section RFI-L, RFA-L, BPF-L to a mixer MIX-L. To obtain a relatively good performance, a band-pass filter BPF-L in the input section can be tuned through a frequency band, in which reception signals of both the first and the second type are present. The filter characteristics of the band-pass filter BPF-L are switched in accordance with the type of reception signal desired. For example, switching provides a passband which is substantially narrower for FM reception than for TV reception.

Abstract: The double tuning circuit of a TV tuner provided by the present invention comprises a primary tuning circuit and a secondary tuning circuit coupled with each other wherein at least one of the primary and secondary tuning circuits comprises two series circuits connected to each other in parallel with each of the two series circuits including damping resistors and/or resonance capacitors in addition to switching diodes which are each selectively turned on and off by using a predetermined switching voltage corresponding to signal reception states so that the frequency response of an intermediate-frequency signal obtained on the output side of the double tuning circuit is fixed independently of a channel receiving the incoming signal and the intensity of the electric field of the incoming signal.

Abstract: A tuner circuit is basically composed of: a series of a low-band coil and a high-band coil disposed on the signal side; a series of a low-band coil and a high-band coil disposed on the earth side; and a switching diode disposed between a junction of the low-band coil and high-band coil on the signal side and another junction of the low-band coil and high-band coil on the earth side. Further, the junction of the low-band coil and high-band coil on the signal side is connected to a band switching terminal via a first bias resistor while an input side terminal of the low-band coil on the signal side is connected with a second bias resistor.

Abstract: A circuit configuration, especially in a television set, for range switching in tuners having at least two ranges includes at least two preselector stages each being assigned a respective tuner range. Each of the preselector stages is connected between a supply potential terminal and a reference potential terminal. Each of the preselector stages has an input terminal, an output terminal and an MOS tetrode. A switchgear for activating each of the MOS tetrodes has a switch output terminal being connected to the preselector stages and being connectable to the reference potential terminal. The preselector stages are coupled to one another for activating one of the preselector stages as a function of a switch state of the switch output terminal.

Abstract: A circuit configuration for range switching in tuners having at least two ranges includes at least two preselector stages each being assigned to a respective tuner range. Each of the preselector stages is connected between a supply potential terminal and a reference potential terminal. Each of the preselector stages has an input terminal, an output terminal and an MOS tetrode with a source terminal. A switchgear has switch outputs to be connected to the reference potential terminal for activating each of the MOS tetrodes. At least one resistor is connected between the source terminal of at least one of the MOS tetrodes and at least one of the switch outputs.

Abstract: An AM/FM band selector is provided for selecting AM and FM bands by a single band switch. By using only a single band switch, power consuming parts are eliminated so that power consumption of the selector is reduced. Also, impulse noise which occurs when selecting bands and switching on and off the power source is removed to provide an efficiently operating AM/FM band selector. The AM/FM band selector having a single band switch prevents simultaneous selection of AM and FM bands.

Abstract: TV-RF input circuit provided with an RF coupling device via which an aerial input is coupled to first, second and third parallel tunable RF resonant circuits (11, 21, 31) for a parallel selection of a desired frequency in first, second and third TV frequency bands (50-160 MHz; 160-470 MHz; 470-860 MHz) substantially succeeding one another in frequency, the RF coupling device having a high-pass .pi.-section (C, L2, L3) for suppressing frequencies below the first TV frequency band and being provided with a capacitive series branch and first and second inductive shunt branches, the .pi.-section (C, L2, L3) being coupled via a first series inductance (L1) to the first RF resonant circuit (11).

Abstract: A television tuner for three different frequency ranges comprises a common antenna connection for three input filter circuits (1, 2, 3). In order to obtain a simple circuit design which involves negligible mutual capacitive loads from the input filter circuits (1, 2, 3), the antenna connection (4) is spatially associated with the input filter circuit (3) for the highest frequency range and is directly connected to one end of a coupling conductor (5). The coupling conductor (5) is series-connected directly with the connection for input filter circuit (1) of the lowest frequency range I and, via a switching diode (11), with the input filter circuit (2) for the medium frequency range II. A further switch (12) detunes the input filter circuit (3) for the highest frequency range III if one of the other input filter circuits (1, 2) is activated.

Abstract: A circuit arrangement of input stages for a television tuner for the UHF, VHF and hyperband frequency bands in a continuous frequency range having primary bandpass filters for the UHF and VHF bands arranged in parallel, and connected to a signal input aerial (7). The input of the VHF primary bandpass filter is coupled to at least one grounded first inductance (27), series-arranged second and third inductances (29 and 31) between the output and the first inductance (27) and a grounded variable capacitor (33) arranged at the output and a first switch (35) which shunts the second inductance (29) and switches between the BI and the BIII ranges of the VHF band.

Abstract: The invention relates to a circuit arrangement for a tuner, particularly a television tuner, for a change over switching between two frequency bands with the aid of a switching diode, said frequency bands, particularly the VHF band and the hyperband, being filtered out by means of bandpass filters (1,7). The bandpass filters have at their inputs and outputs capacitance diodes for the purpose of tuning. The filtered signals are applied to a common tunable circuit (15) on the secondary side of the bandpass filters. The bandpass filter for the hyperband is constructed and dimensioned such that the signal is switched through by means of a switching diode (83) arranged at the low end of the bandpass filter (1). When this diode (83) is conducting a smaller output reactance, whereas in the case of a blocking switching diode (83), this bandpass filter (1) cuts off the signal and has a larger output reactance.

Abstract: The channel selector shaft of a 70 channel mechanically detented UHF tuner is provided with mechanical stops which prevent the shaft from moving above UHF channel No. 69 so that the upper twenty-four UHF channels are unused. Also, a dial driving arrangement is provided for driving an expanded UHF dial having only 56 channel indicia so that the 56 channel indicia cover substantially the same area on the dial as the 70 channel indicia of prior art arrangements.

Abstract: A band switching circuit for a tuner for receiving VHF and UHF channels comprises a tuning circuit including a switching diode having an anode and a cathode for band switching, a plurality of resistors connected to the anode and cathode of the switching diode to thereby form a series-connected circuit, and a second diode connected in the series-connected circuit in a direction opposite to that of the switching diode. The switching diode can be forward-biased or reverse-biased for receiving the VHF channels, and can be disconnected from a DC power supply for receiving the UHF channels.

Abstract: A combination UHF-VHF tuner has a switching diode placed in series with a VHF high-range peaking coil so that the coil forms a parallel resonance peaking circuit when high-range VHF signals are received and the coil acts as a series impedance matching element when a UHF IF signal is coupled from a UHF mixer stage.

Abstract: An input circuit comprises at least two input paths which are connected to a common input terminal and which are alternately connectable to a common output. The input paths form selection members for the UHF and VHF frequency range whose signals are amplified in a common preamplifier component. In order to avoid mutual influencing of the selection members with simple measures, the output of the VHF selection member is connected to the common output via an impedance of the UHF selection member and a switch is provided for connecting the impedance and the output of the VHF selection member to ground for high frequency. The switch is conductive during UHF operation and then short circuits the output of the connected VHF input path.

Abstract: The invention relates to a two-circuit resonant bandpass filter for television tuners for switching a first frequency band to a second frequency band. The bandpass filter has a common primary circuit to which two secondary circuits are coupled, a first of the secondary circuits being connected via an electronic switch to the primary circuit which, together with the reactances of the first secondary circuit, short circuits, in the closed condition, the second secondary circuit.

Abstract: An electronic tuner capable of selectively receiving the UHF band and high and low channels in the VHF band is described which has a suitable resistance provided across power supply terminals in order to improve the separation between the VHF mode and the UHF mode.

Abstract: A rotary type television tuner includes a chassis and a channel changing shaft extending through the chassis and having an operating knob mounted on the front end thereof for rotating the shaft. The channel changing shaft is made of a synthetic resin reinforced with glass fiber and is circular in cross-section over the greater part, the knob mounting section being formed with a flat portion and having a cross-section that is nearly semicircular. The root of the flat portion of the knob mounting section is rounded. A reinforcing rod assembly comprising a reinforcing rod made of a metal and a reinforcing rod made of a rigid synthetic resin which are connected together as by threads is embedded in the channel changing shaft including its knob mounting section. The length of the reinforcing rod of metal is such that when it is assembled as the tuner, it extends from the front end nearly to the chassis plate.

Abstract: A channel-selecting, presettable, rotary type tuning device in which there is provided a tuning-position-determining unit having two or more tuning-position-determining elements, whose positions may be adjustable; a slide member operably coupled to a variable tuning element and spring-loaded so as to abut the end of each tuning-position-determining element selected due to the rotation of the tuning-position-determining unit; means for rotating the tuning-position-determining unit so as to select a tuning-position-determining element; means for moving back and forth each tuning-position-determining-element thus selected; and means for temporarily releasing the slide member from its abutment on each tuning-position-determining element thus selected.

Abstract: An operator-controllable detent mechanism is provided for a combination VHF-UHF television tuner. Separate torsionally-loaded detent springs are provided for two detent wheels which are mounted on the common station selector shaft of the tuner. A manually-operable control member concentric with the selector shaft is employed selectively to remove the torsional load on one detent member or the other so that the common selector shaft may be detented for combined VHF-UHF reception, VHF only reception or UHF only reception.

Abstract: In a VHF tuner a stator bar switching arrangement is provided which is particularly suitable for use in combination VHF-UHF tuners. A movable switching member positioned on the main stator bar of a turret type VHF tuner is moved between fixed contacts on the stator bar by engagement with a projection on each of the tuning sticks of the turret in each VHF channel receiving position of the main selector shaft. Various switching arrangements are provided for VHF-UHF operation.

Abstract: A combination VHF, UHF and superband tuner, the superband and UHF tuners cooperating with the Channel 1 section of the VHF tuner, is provided with a connection network including voltage sensitive switching devices, such as voltage sensitive diodes, so that selectively energizing a particular desired tuner by applying a supply voltage thereto will automatically effect the appropriate interconnections between the tuning units to render the selected tuner operatively effective and the non-selected tuners non-interfering therewith.

Abstract: A method for cleaning the fixed spring-contacts of a cylindrical, drum-type television tuner or other electrical switch having contact-carrying strips arranged around the circumference of a rotatable drum, in which a cleaning implement is attached to the drum and is rotated into engagement with the fixed contacts so as to clean the same. The implement includes a support for attachment to the drum and a cleaning element on the support for engaging and cleaning the spring-contacts of the switch upon rotation of the drum. The cleaning element may be a set of eraser pads, an elongated eraser strip, or a coating or layer of abrasive material; and the support element may be made for the attachment to the drum either in superposition with an operative contact-carrying strip or in lieu thereof.

Abstract: A continuously variable UHF tuner arrangement is provided wherein a single channel selector shaft is provided with a detent position for each of the 70 UHF television stations and a highly accurate detent mechanism is employed to return the channel selector shaft to any one of the detent positions with extreme accuracy. As a result, the tuning elements of the tuner may be accurately aligned to different UHF stations corresponding to said detent positions and a nonambiguous digital dial arrangement may be employed to indicate to the operator exactly which UHF station is being received. Electronic fine tuning is provided to permit the UHF tuner to be fine tuned independently of the position of the selector shaft.

Abstract: A frequency band selection switch and variable resistor assembly for one channel of a television tuner in which tuning is performed by varying a tuning voltage. A tuning shaft is connected to the slider of the variable resistor through a harmonic drive reduction gear assembly. A tuning scale is connected to the slider through a bored tuning scale shaft through which the tuning shaft coaxially extends. A bored switch shaft through which both the tuning and tuning scale shafts coaxially extend carries a movable contact of the band selection switch and a frequency band indicator. An assembly support member has a graduated dial associated with both the tuning scale and the frequency band indicator in a unitary manner.

Abstract: A control circuit is disclosed to automatically tune an antenna coupler to provide an output signal having a selected one of different operating frequencies. The antenna coupler includes a frequency band selecting switch and a plurality of tuning elements certain or which are available to provide the desired output signal. The switch is controlled by a first relay controlled motor and the variable tuning elements are controlled by a second relay controlled motor. First logic circuitry is coupled to the first and second motors to control the tuning of the antenna coupler sequentially through a preposition step, a tuning step and an antenna coupler ready step. An amplitude comparator having a given capture range has its input coupled to the antenna coupler and second logic circuitry is coupled to the amplitude comparator, the first logic circuitry and the second motor.