METHOD FOR PROTECTION AGAINST UNAUTHORIZED EAVESDROPPING IN INTERVALS BETWEEN TELEPHONE TALKS AND DEVICE WHICH IMPLEMENTS SAID METHOD Russian patent published in 2000 - IPC

FIELD: security equipment, in particular, protection against eavesdropping equipment using telephone line for transmission of information or as power supply or as information source about line condition for making decision about eavesdropping. SUBSTANCE: method involves automatic alteration of electric parameters at user's end of telephone line under protection. Said line passes through room to be protected and ends with standard telephone set. Remote actuating unit, which is inserted into telephone line outside of room under protection, provides disconnection of user's end of input telephone line for period when telephone line is not used for telephone talks. Device also provides connection in automatic mode according to commands which enter actuating unit from control unit, which is located directly in front of telephone set, so that connection is restored while call signals from exchange system are received or during talk. When telephone talk or call signals are finished, device disconnects user's terminal end of telephone line under protection from telephone line. EFFECT: increased functional capabilities. 3 cl, 5 dwg