DEVICE CONTROLLING DIGITAL TELEPHONE SET Russian patent published in 1999 - IPC

FIELD: electrical communication. SUBSTANCE: invention can find use in digital telephone sets placed in digital telephone networks where information is fed to telephone set and comes from it in digital form. According to preferable version device has unit switching codec on and off and signal analyzing unit incorporates shift register of input signals, first comparison circuit with first storage of code of sign of information signal. Output of shift register is connected to input of first comparison circuit whose second input is coupled to output of first storage. Output of first comparison circuit is connected to first controlling input of unit switching codec on and off which third output is connected to first controlling input of scrambler. In correspondence with another version proposed device has signal analyzing unit that includes second and third comparison circuits with codes of test and call correspondingly. Invention provides for switching codec and correspondingly scrambler on for the time of presence of information signal and for switching of codec of digital telephone set and scrambler off when there is no such signal with simultaneous protection of device against false operation. It also ensures consumption of energy required only by codec and scrambler. EFFECT: improved operational characteristics of device. 2 cl, 2 dwg