TELEPHONE SET CIRCUIT

PURPOSE:To prevent a trouble of rining call signal by applying a call tone sounding larger gradually to a receiver of a caller so as to urge the disconnection of a caller when the incoming side does not respond. CONSTITUTION:When a caller hooks on a hook switch 6 and dials a telephone number of the opposite party by using a dial circuit 4, a call tone is inputted from a circuit A for a while. A call tone detection circuit 7 detects a call tone and starts a timer circuit 8 and outputs plural outputs Q1-Qn at each prescribed time. The amplification factor of an amplifier 9 is larger by the outputs Q1-Qn, then the caller is urged for disconnection with a call tone larger as the calling time becomes longer.