TELEPHONE SYSTEM

摘要

PURPOSE:To send out a signal to a slave telephone set requesting to interrupt speech when an emergency call is desired on a master telephone set but the master telephone set is disabled to use due to the busy of the slave telephone set or when a person to whom an emergency message is desired is busy. CONSTITUTION:A ring tone signal is generated when an emergency information key 11 is depressed while the master telephone set 1 is connected to the emergency information key 11 and the slave telephone set 2 to a telephone line 4 in a cordless extension telephone set in which the slave telephone set 2 is busy. A control circuit 14 sends out the ring tone signal to the slave telephone set 2 via a transmission circuit 7.