HIGHLY SENSITIVE VIBRATION RECEIVER Russian patent published in 2000 - IPC

FIELD: geophysics, seismology, physics, in particular, electroacoustic transducers. SUBSTANCE: a capacitor is cut in the inductive circuit, and pumping via a matching device-Ac generator. At a respective selection of the pumping frequency, resonant frequency formed by the inductor and capacitor of the electric circuit with respect to the frequency of external mechanical disturbance, a three- frequency mode of parametric amplification of input vibrations is realized in the receiver second circuit. The receiver sensitivity is enhanced due to the low-noise force peculiar to parametric amplification, increase of the transfer ratio of the receiver input circuit at conversion of vibrations to electric oscillations and due to a shift of the frequency of amplified oscillations to the radio-frequency region, where the intensity of many components of receiver noise is lower than that in the range of input audio-frequency oscillations. EFFECT: enhanced receiver sensitivity. 2 dwg