摘要 |
In a telephone circuit equipted with an anti-sidetone circuit of the type comprising a transmitter, a receiver, a balancing network, and a hybrid coil intercoupling the transmitter, the receiver, and the balancing network, an artificial subscriber's line including a non-linear resistance element which varies its resistance in accordance with the voltage across the telephone lines is connected between the telephone lines and the telephone circuit, a non-linear capacitance element which varies its capacitance in accordance with the D.C. voltage across the telephone lines is included in a balanced circuit network, and a constant direct current device is connected in series with the transmitter. |