| 摘要 |
FIELD: acoustic security alarm devices. SUBSTANCE: device has sensitive member, for example microphone, low-pass filter, sound frequency amplifier, linear divider which has resistors of first and second regulation stages, comparator, integrating circuit, Schmidt flip-flop, inverter and negative feedback circuit. Low-pass filter is connected to input of sound frequency amplifier, which output is connected to one input of comparators. Another input of comparator is connected to output of sound frequency amplifier through linear divider and to output of negative feedback circuit. Output of comparator is connected to input of negative feedback circuit through integrating circuit, Schmidt flip-flop and inverter. Output of inverter is output of device. Device may be used for guarding rooms with closed entries, for example for guarding home and office rooms, cars. Device provides possibility to exclude device firing when animals and persons are located in near by of tested area. EFFECT: increased functional capabilities due to increased sensitivity, increased selectivity of amplitude of electric signal. |
