Abstract: A multiplexed audio-video signal transmission system has a camera-equipped intercom which produces a balanced audio-video signal. A twisted pair-wire connected to the intercom transmits a multiplexed signal of audio signal, video signal modulated to a frequency band not overlapping the audio signal frequency, and DC power. The audio signal and video signal are carried in the pair-wire in opposite phase in a balanced condition, and the DC power is carried between the pair-wire. A relay device is inserted in the pair-wire to refine the video signal. Main line branching device and door branching device are provided to branch out the multiplexed signal to a television equipped control unit 17.

Abstract: A multiplexed audio-video signal transmission system has a camera-equipped intercom which produces a balanced audio-video signal. A twisted pair-wire connected to the intercom transmits a multiplexed signal of audio signal, video signal modulated to a frequency band not overlapping the audio signal frequency, and DC power. The audio signal and video signal are carried in the pair-wire in opposite phase in a balanced condition, and the DC power is carried between the pair-wire. A relay device is inserted in the pair-wire to refine the video signal. Main line branching device and door branching device are provided to branch out the multiplexed signal to a television equipped control unit 17.

Abstract: A communication control device and method for an information transmission system which can set automatically its self-address. When the device is connected to the system, candidate values set as destination addresses are sequentially sent from the device to the system. If no response is obtained from the system even when a candidate value is sent to the system, the candidate value is set as the self-address of the device.

Abstract: Operation information for distinguishing each operation of a wireless signal transmitter of a remote control system is included in a wireless signal of the wireless signal transmitter, the operation information is memorized in an AV apparatus which is designated by the wireless signal transmitter, and the wireless signal or only one of plural message frames which have the same information as the wireless signal and are transferred from other AV apparatus connected to a common communication line is selected by comparing the operation information of the message frame with the memorized message frame in the AV apparatus.

Abstract: A communication controller in a home bus system comprises a single pulse transformer having two secondary windings connected respectively to a coaxial cable and a pair of wires, to which a personal computer, a television receiver, a sensor, etc. are connected. The controller is provided for transmitting a communication packet to the coaxial cable or the pair of wires and the system automatically transmits the communication packet from the pair of wires to the coaxial cable or vice versa.