Abstract: A communication system having an automatic dialer, which generates a signal for selection of a communication line from a plurality of communication lines belonging to a plurality of common carriers before communication is made between a calling subscriber and a called subscriber. The automatic dialer automatically transmits the signal for specifying one of a plurality of signal paths coupled to the called subscriber in addition to other necessary signals. The necessary signals may be automatically transmitted with the minimum dial number, resulting in easier operation of the system.

Abstract: An automatic dialer, which generates a signal for selection of a communication line from a plurality of communication lines belonging to a plurality of common carriers before communication is made between a calling subscriber and a called subscriber. The automatic dialer automatically transmits a signal specifying one of a plurality of signal paths coupled to the called subscriber in addition to other necessary signals, thus minimizing the numbers dialed by a user and resulting in easier operation of the system. The ones of the plurality of signal paths specified by the system can be easily changed by a tone sent to the system.