FIELD: commercial and industrial espionage counteraction technologies.
SUBSTANCE: device contains, serially, connected, auxiliary microphone, amplifier, amplitude detector, controllable generator of sound spectrum interference and an electro-acoustic unit. Also present are serially connected auxiliary antenna and detector of radio-radiation of a cell phone. Auxiliary antenna is mounted with possible receipt of cell phone radiation as working signal, when cell phone is switched to radio transmission mode. Auxiliary microphone (2) is mounted with possible perception of speech signals subject to unsanctioned listening. Electro-acoustic unit (6) is made with possible operation in loudspeaker mode sending acoustic noise into cell phone microphone when lowered into hollow of device case and in microphone mode with perception of call signal of cell phone during normal call. Device additionally features a detector of a cell phone call signal, connected by its input to electric output of electro-acoustic unit, and a XOR-NOT element, inputs of which are connected to outputs of detectors of radio-radiation and call signal of cell phone, and output - to launch input of interference generator. Component units of device are positioned in common case, which has a hollow for installation of cell phone with commutation of power supply switch under effect from its gravity force. Invention ensures absence of acoustic noise when no attempts of unsanctioned listening of confidential conversations are made and during normal call of cell phone by other phone number, and also control over interference generator with resulting proportionality of acoustic noise level to the level of speech signal.
EFFECT: increased comfort for participants of conversation with a cell phone mounted in the room.
5 cl, 1 dwg
