Three person telephone call hitting adjusting circuits null of time sharing Takata direction

摘要

PURPOSE:To make a three-party telephone call stable in speech level by providing a level controller which controls the level of a speech signal from a master station to a slave station and a phase shifter which makes a phase difference between two speech signals from the master station to the slave station. CONSTITUTION:The speech signal from the master station 1 to a handset 10 is supplied to the level controller 30 to control the speech signal level of the master station 1 and the speech signal levels of slave stations 2-1-2-N to which signals are transferred to the same level; and the speech signal input is supplied to a hybrid transformer 13-1 and distributed in two directions and they are given a 120 deg. phase difference through phase shifters 31-1 and 31-2. One speech signal which has the phase difference is mixed with the speech signal of the slave station 2-1 in a speech state by a hybrid transformer 13-2 and the mixture signal is sent out to the slave stations 2-1-2-N. Therefore, the master station 1 and slave stations 2-1 and 2-2 can intercept a three-party talk at a normal speech level without receiving speech signals that they sent out by themselves.