Abstract: This invention discloses a digital wireless speaker system for use in consumer audio applications. A digital radio frequency transmitter is connected to an analog or digital audio source and a digital radio frequency receiver provides for reception of the transmitted audio information in remote locations. In addition, the digital receiver will be able to receive control information to implement such things as volume, tone controls, or other auxiliary information. This allows the user to listen to high quality audio in a variety of locations without the need of independent stereos or external wires. The system is based on digital circuitry to improve the performance of the system and provide for compact disc quality sound. The digital circuitry incorporates forward error correction techniques and interleaving to enable the system to account for errors in transmission and thus improve the overall performance of the system.

Abstract: This invention discloses a digital wireless speaker system for use in consumer audio applications. A digital radio frequency transmitter is connected to an analog or digital audio source and a digital radio frequency receiver provides for reception of the transmitted audio information in remote locations. In addition, the digital receiver will be able to receive control information to implement such things as volume, tone controls, or other auxiliary information. This allows the user to listen to high quality audio in a variety of locations without the need of independent stereos or external wires. The system is based on digital circuitry to improve the performance of the system and provide for compact disc quality sound. The digital circuitry incorporates forward error correction techniques and interleaving to enable the system to account for errors in transmission and thus improve the overall performance of the system.

Abstract: An analog spread spectrum wireless speaker system for use in consumer audio applications for providing reliable and high fidelity stereo sound. The system includes a transmitter that accommodates any analog input from a variety of audio devices such as compact disk players, cassette players, AM/FM tuners and transmits this information in the 2.4-2.4835 GHz band to a receiver at a remote location. The receiver is capable of reproducing the audio signal with good frequency and signal-to-noise performance.

Abstract: A system is provided which transmits either analog or digital data signals over the air. The system includes a transmitter and a receiver. The transmitter and receiver are arranged to transmit signals using a carrier signal having a high frequency such as in the range of 902-928 MHz. The transmitter and receiver are configured to provide for the transmission of two channels of stereophonic signals while maintaining high signal-to-noise ratios, good frequency response, and low distortion. To provide for the proper transmission of signals between transmitter 10 and receiver 12, these devices include oscillating circuits having ceramic resonators which provide a base frequency which is readily modulated to facilitate proper transmission of either analog or digital signals between the transmitter and receiver.

Abstract: A system is provided which transmits either analog or digital data signals over the air. The system includes including a transmitter and a receiver. The transmitter and receiver are arranged to transmit signals using a carrier signal having a high frequency such as in the range of 902-928 MHz. The transmitter and receiver are configured to provide for the transmission of two channels of stereophonic signals while maintaining high signal-to-noise ratios, good frequency response, and low distortion. To provide for the proper transmission of signals between transmitter 10 and receiver 12, these devices include oscillating circuits having ceramic resonators which provide a base frequency which is readily modulated to facilitate proper transmission of either analog or digital signals between the transmitter and receiver.

Abstract: Apparatus for enabling or disabling a selected telephone. A control signal having a unique predetermined frequency, which corresponds to a desired state of the selected telephone, is transmitted from a transmitter through standard telephone lines. The telephone is connected to a receiver, having one of a plurality of resonant circuits each tuned to one of the unique predetermined frequencies, which receives the control signal. When the frequency of the control signal matches the tuned frequency of a resonant circuit, the receiver connects or disconnects accordingly the selected telephone from the telephone lines thereby enabling or disabling, respectively, the selected telephone.

Abstract: In order to utilize standard tape players in automobiles to play compact disks, CD adapters are provided which play the CD output through the tape system of the automobile. This invention provides an in-line audio enhancement encapsulated device, manually operable by a driver to switch in the audio enhancement circuitry and adjust the audio signals produced in an efficient and safe manner so that it can be operated while a car is driven without the driver taking his eyes off the road. A bass boost circuit (24) is specifically disclosed to enhance the low frequency audio signals procuced by the automobile's audio system.

Abstract: A tuned radio apparatus includes a tuned radio receiver and a tuned antenna apparatus both of which are tuned to the same frequency. The antenna apparatus may include a varactor similar to a varactor used in the receiver and receiving the same tuning voltage for tuning at least one antenna. The tuning voltage may be supplied from the receiver to the antenna apparatus and the received radio frequency output may be supplied from the antenna apparatus to the receiver over an antenna cable connected to a single antenna terminal.

Abstract: A repeater for receiving data transmitted thereto via a first transmission medium, transmitting that data over AC power lines to a remote location and re-transmitting that data from the remote location via a second transmission medium. The data is applied to the AC power lines by frequency modulating an FM carrier and supplying that modulated carrier to the power lines by way of a bandwidth limiting circuit. At the remote location, a resonant circuit in combination with a reject circuit receives the modulated FM carrier from the AC power lines and passes only an extremely limited band of FM signals to a tuned amplifier which, in turn, supplies the band-limited FM signals to a demodulator.

Abstract: An antenna assembly which is suited for receiving FM signals, comprises a pair of insulating disc shaped substrates which each have conductive patterns deposited on one surface thereof. The first insulating substrate has an electrically conductive loop element extending around approximately 360.degree. on the first substrate. The loop element terminates at first and second terminals which are adjacent each other. An electrically conductive tap element is deposited on one surface of the second substrate. The tap element extends around approximately 180.degree. and is parallel to half of the length of the loop element. On end of the tap element is electrically connected to a mid-point of the loop element intermediate its first and second terminals. Plate areas are deposited on the substrate and are electrically connected to selected terminals of the loop and tap elements to form capacitors.

Abstract: A device comprised of separate transmitter and receiver sections, which converts an audio signal into an FM signal, transmits the FM signal over AC power lines, and reconverts the FM signal into an audio signal, which can then be outputted to loudspeakers or other devices. By transmitting the signal over AC lines, no long wires are needed to connect remote loudspeakers or other devices to the source of the audio signal.

Abstract: A device comprised of separate transmitter and receiver sections, which converts an audio signal into an F.M. signal, transmits the F.M. signal over A.C. power lines, and reconverts the F.M. signal into an audio signal, which can then be outputted to loudspeakers or other devices. By transmitting the signal over A.C. lines, no long wires are needed to connect remote loudspeakers or other devices to the source of the audio signal.

Abstract: An adapter is provided for use with a television receiver to detect and decode stereophonic audio signals, SAP signals or auxiliary signals that may be transmitted with the composite television signals. The adapter includes an IF input that is physically separate from the television receiver for receiving IF audio signals that normally are derived from the transmitted composite telephone signals. Detecting circuitry is coupled to the IF input by means of a tuned circuit that is tuned to the IF carrier frequency of the received IF audio signals for detecting the stereo, SAP or auxiliary signals transmitted with the composite television signals. The detected signals are used to drive utilization means, such as loudspeakers. Preferably, switches are provided to select the stereo or SAP or auxiliary signals for detection.

Abstract: An adapter for enabling the signals produced by one type of playback device, such as a compact disc player, to be reproduced as audio sounds by a cassette player audio system, the latter having a conventional cassette playback deck. The adapter is comprised of a housing having a configuration substantially identical to the configuration of a cassette normally used with the playback deck. The adapter housing has at least one opening to receive the usual reel-drive spindle of the playback deck; and a record head is supported in the housing in a position for contacting the usual playback head of the deck when the adapter is received, or loaded into that deck. The adapter is connected to the playback device (e.g. the compact disc player) by a plug connected to the usual headphone jack of the player, whereby signals produced by the player are supplied to the record head from which they are coupled to the playback head of the cassette deck for reproduction by the audio system.

Abstract: A television stereo adapter is provided for use with a television receiver to detect and decode stereophonic audio signals that may be transmitted with the composite television signals. The adapter includes an IF pick-up that is physically separate from the television receiver for picking up spurious IF audio signals that normally are generated by the television receiver. A stereo detector is coupled to the IF pick-up for detecting from the IF audio signals monophonic and stereophonic components that are transmitted with the composite television signals. The detected components are decoded into left-channel and right-channel audio signals; and these left-channel and right-channel signals are adapted to drive sound transducers, such as loudspeakers. Optionally, the left-channel and right-channel audio signals are amplified by gain-controlled amplifiers whose gains are a function of the output sound level of the television receiver.

Abstract: A stereophonic receiver includes internal separation control in which the sound separation is directly in accordance with noise reduction need and the amplitude and frequency of the sound signals monitored. Each sound channel is similar and includes an input buffer and an output buffer to directly transmit the corresponding channel signal. A variable highpass filter unit interconnects the output buffer of each channel to the opposite channel, and includes a voltage sensitive input to control the transmitted signal level. A control channel includes a high frequency filter to pass the high frequency signal of the stereophonic sound, which signal is rectified and filtered by suitable attack and decay filters. A log-conversion unit senses and converts the filtered signal to a C. logarithmic D.C. signal, which is directly proportional to the amplitude and frequency of the corresponding channel stereophonic signal. The D.C.

Abstract: An FM tuner control circuit contains a digital frequency synthesizing control circuit, digital computer means including a microprocessor, a memory circuit, and a manual control circuit for digitally tuning the tuner to any desired FM station. The memory circuit includes a read-only memory containing programs for the microprocessor and a random-access memory in which a group of predetermined station frequencies can be stored. The control circuit also includes a call letter display circuit, a frequency scale pointer display circuit, a frequency display circuit, a manual tuning circuit, and remote control switches for the manual control circuit.

Abstract: An FM tuner control circuit contains a digital frequency synthesizing control circuit, digital computer means including a microprocessor, a memory circuit, and a manual control circuit for digitally tuning the tuner to any desired FM station. The memory circuit includes a read-only memory containing programs for the microprocessor and a random-access memory in which a group of predetermined station frequencies can be stored. The control circuit also includes a call letter display circuit, a frequency scale pointer display circuit, a frequency display circuit, a manual tuning circuit, and remote control switches for the manual control circuit.

Abstract: An audible alarm is set off by unauthorized opening of a vehicle's doors, trunk or hood. The alarm circuit includes an operational amplifier and means coupling both operational amplifier inputs to the ungrounded vehicle battery terminal through balanced input resistors. A capacitor is coupled between one operational amplifier input and ground. When the door or trunk is opened, a light is automatically switched on, thus causing the battery voltage to drop slightly and producing an output signal from the operational amplifier which energizes an audible alarm coupled thereto. A key switch which is accessible from the outside the vehicle can be turned to disable the alarm circuit to permit authorized entry of the vehicle. The differential input of the operational amplifier stabilizes the circuit's operating characteristics with respect to temperature and prevents malfunction at temperature extremes.

Abstract: A solid state electronic system for producing a variable time delayed echo signal from a source of electro-audio input signals including circuitry for reducing noise. For low level signal operation, the system has means for varying the internal reference to thereby require twice as many digital bits to correspond to a given analog signal input amplitude thereby doubling the resolution when operating in said low signal mode.