PRIVACY COMMUNICATION DEVICE

PURPOSE:To provide numbers of key codes for a request to secure privacy and prevent communication contents from being intercepted when they are received by the 3rd party by providing a privacy communication device with a variable delay circuit, frequency dividing circuit, counter circuit, and logical circuit. CONSTITUTION:The speed signal from the speech input terminal 1 of the privacy communication device is applied to the BBD delay circuit 3 through an LPF2, and the speed signal is sampled according to the clock of a clock circuit 4 and stored in the delay stage of the circuit 3. Then, those 2N sampled values which are stored are passed through an LPF5 and added by an adding circuit 7 to the output of a synchronizing signal circuit 6, and the sum is frequency-modulated by a transmitting circuit 8 and sent to a transmission system 9. This signal is demodulated by a receiving circuit 10 and applied to a BBD delay circuit 14 through an LPF11 to sample and store the receive speech according to the clock of a clock circuit 12. At the same time, sampled values which 2N samples before are outputted from an LPF13 in order simultaneously. Those circuits 4 and 14 are provided with a master clock oscillaor 17, frequency dividing circuit 18, counter 19, and logical circuit 20.