Rca Inc.

Rca Licensing Corporation

David J Carlson

William L Lehmann

Juri Tults

Harold Blatter

John P Yu

Sander H Tsou

Jeffrey G Lea

Antenna coupling components including a coil and a static discharge resistor are mounted on a separate printed circuit board within a tuner that is positioned by means of projecting tabs on each end so as to self-center the coil with the inductor. A first tab extends through an aperture in the tuner wall and carries foil patterns for connecting an antenna to the coil and one end of the resistor. The other tab is secured to a slot in an internal shield to provide mechanical support for the board, electrical connection to ground for the other end of the resistor and which facilitates lateral movement of the coil during assembly. A connector block, fixed to the outside of the tuner enclosure, provides mechanical support and electrical insulation for the first tab and additionally provides electrical connection to a pair of antenna terminals and a right angle bend in the antenna circuit.

Tuner with insertable antenna coupler

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.

Television receiver for direct broadcast satellite signals

An apparatus is disclosed which presents a high impedance to unwanted RF signals which may be otherwise coupled to jumper wires which traverse the boundary between RF shielded areas. Specifically, a conductor for connecting two circuits separated by a shield wall is surrounded by a ferrite material which is positioned to extend through an aperture of the RF shield.

Isolation of RF signals in a RF shield aperture

A quasi-parallel IF television receiver derives the AFT voltage from a video carrier in the sound IF channel. Since the signals in the sound IF channel do not pass through the VSB filter, asymmetries in the AFT loop response are avoided. This results in better operation of the AFT control loop.

Dual channel IF TV receiver with AFT derived from the picture carrier in

In a double conversion tuner for a television receiver including a first local oscillator and a first mixer for converting the RF signal corresponding to a selected channel to a first IF signal and a second local oscillator and a second mixer for converting the first IF signal to a second IF signal, control apparatus is coupled to one of the local oscillators for offsetting its frequency and correspondingly the carriers of the first IF signal relative to the passband of a first IF filter coupled between the two mixers. In this manner the amplitude or phase of the carriers of the first IF signal can be controlled. An AFT signal is coupled to the other one of the local oscillators to compensate for the frequency offset of the carriers of the first IF signal in order to tune the carriers of the second IF signal to their nominal frequencies.

Double conversion television tuner with frequency response control

A double conversion tuner stabilized against drift includes a first local oscillator included in a phase locked loop (PLL) and a second local oscillator included in an automatic fine tuning (AFT) loop. A switching arrangement selectively allows the AFT signal to control the second local oscillator only when the operation of the PLL has been completed and if the picture carrier of the IF signal produced at the output of the tuner is within the AFT control range to prevent the second local oscillator from being tuned incorrectly.

AFT arrangement for a double conversion tuner

A double conversion television tuner has first and second mixers and uses both the sum and difference frequency signals from the second mixer. The picture component of the difference frequency is separated from the output of the second mixer using a first filter and then demodulated. A second filter passes the sum frequency signal and the second harmonic of the nominally fixed frequency local oscillator signal applied to the second mixer. A third mixer is coupled to the second filter and mixes the converted sum frequency signal with the second harmonic signal. The audio component of the resulting sound signal is demodulated. Because the sum and difference signals at the output of the second mixer are far apart in frequency, the first and second filters can be easily designed so as not to interact.

Double conversion tuner with split IF output

Selection elements such as diodes or filters are provided for selectively grounding either one of the two unbalanced terminals of a balun. This allows either a signal, such as the R.F. signals from a VHF or a UHF antenna, applied to the other unbalanced terminal of the balun to be selectively coupled to the balanced terminals of the balun in a diplexer arrangement. In a tuner, the balun may be used as part of a doubly balanced mixer. In another embodiment, the balanced terminals are used as inputs and the unbalanced terminals are used as outputs with the selection elements coupled to the outputs to form an R.F. multiplexer.

R.F. Diplexing and multiplexing means

A tunable oscillator develops a signal having a frequency variable over a range of frequencies in response to a control signal. A frequency determining resonant circuit includes two voltage-variable capacitance diodes in an arrangement for adjusting at least one endpoint of the frequency range. As a result, the relationship between the magnitude of the control signal and the frequency of the oscillator signal can be adjusted while avoiding mechanically adjustable reactive elements. The disclosed arrangement is suitably employed with resonant circuits other than those in oscillators.

Variable frequency U. H. F. local oscillator for a television receiver

A remote control system utilizing a portion of a television receiver system to control appliances external to the television receiver. A specific embodiment is shown for controlling a telephone through the television remote control unit. The viewer answers or originates telephone calls by operating the television remote control unit. In an alternate embodiment, the signal carrier from the control unit to the television is modulated in order to transmit voice signals. Further appliances may be controlled through the telephone line or by other connections to the television receiver.

Television remote control system for selectively controlling a plurality

In a phase locked loop tuning system including a prescaler for dividing the frequency of the local oscillator signal by a factor selected to make the resultant frequency divided signal compatible with digital processing portions of the tuning system, a frequency selective network is coupled to the prescaler to tune the self-oscillation frequency of the prescaler to a frequency not corresponding to the local oscillator frequency of any legitimate channel. In this manner, when a new channel is selected and the amplitude of the local oscillator signal is below the threshold at which the prescaler will respond to it, the phase locked loop will properly control the local oscillator, rather than respond to a self-oscillation signal which may otherwise correspond to the local oscillator frequency for the selected channel.

Phase locked loop tuning system including a prescaler conditioned to

An antenna coupling network for supplying VHF television carriers to a VHF tuner of a television receiver and weather band carriers to a tuner of a weatherband radio incorporated in the television receiver from a single monopole antenna without adverse interaction simply comprises a first wire connected between the monopole antenna and the VHF tuner and a second wire wrapped around the first wire a predetermined number of times and connected at one end to tuner of the weatherband radio. The number of turns are selected to form a series resonance at a midpoint of the weather band. Desirably the other end of the second wire is left unconnected.

Multi-band antenna coupling network

A coaxial RF connector adapted for mounting on a wall of a utilization device, such as a video disc player, employs a capacitor for providing DC and low frequency blocking between the wall of the device and the outer conductor of the connector. The capacitor is formed in the shape of a washer to provide a uniformly distributed capacitance around the outer conductor.

RF Connector assembly with low frequency isolation

A battery powered ultrasonic remote control transmitter for controlling various functions associated with a television receiver, or the like, includes an arrangement for providing an audible indication that the battery voltage has fallen below a desired operating level. In one embodiment, when the battery voltage has fallen below the desired level, the electrical control signal for at least one control function is selectively amplitude modulated by an audio frequency signal before being coupled to the ultrasonic transducer. As a result, when the control function is selected, an operator is given an audible indication that the battery needs recharging or replacement.

Growing community of inventors

Indianapolis, IN, United States of America

David J Carlson