DEVICE FOR MEASURING SOUND PRESSURE Russian patent published in 2006 - IPC G01L9/12 

FIELD: engineering of devices for measuring sound pressure.

SUBSTANCE: device contains sensor with capacitive sensitive element. Indicator with charge amplifier is connected by anti-vibration cable to screen, which is in turn connected to local grounding. Sensor polarization voltage is fed try resistors R1,R2, which are connected serially between one another. End of screen by wire is connected through capacitor C1 with resistors R1, R2 forming a "star", while another end of resistor R2 is connected to positive pole of polarization source. Charge amplifier is protected from influx of high voltage of polarization source by means of serial connection of first capacitor C2 of pressure sensor and charge amplifier, input of which is connected to resistor R3 and capacitor C3 of check connection. Device with capacitive indicator of sound pressure allows usage of one cable both for polarization of sensor and for measuring output signal, due to provided compensating circuit formed of resistors R1,R2 and second capacitor C1. Electric circuit containing resistors R1, R3 and capacitor C1 isolates capacitors of sensor from capacitor of cable.

EFFECT: increased sensitivity and reliability for measuring low levels of sound pressure at extensive distances.

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