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The amplitude response of a LCR gravimeter with the SRW-E feedback was determined on a vertical vibrating platform. The ink-pen recorder was connected parallel with the digital voltmeter input to obtain an analog response of the gravimeter to the harmonic motion of the base with a peak-to-peak amplitude of 10 pm and periods excited in an interval of 4 -10 s as by the ground motion of meteorological microseisms, and in the interval 10 -100 s as by surface waves of distant strong earthquakes.In the first interval, an unexpected maximum of the amplitude response was observed with the double amplitude of apparent 6,5 /jGal (6.5 x 10-8 m/s2) at a period of 4.8 s, and a baseline shift with the amplitude of-64 juGal was observed at the same period. The value of this direct component cannot be separated from the effect of the Earth's gravity field. In the second interval, the amplitude response of the gravimeter displayed one expected maximum at a period of 40 s with the double amplitude of 8.1 jGal. At the usual level of microseisms with a peak-to-peak amplitude of up to 2 um the fluctuation of the gravimeter on the direct baseline shifted by -4.9 &al was estimated at 1 iGal. With typical Rayleigh surface waves with periods of 20 s and double amplitudes of up to 100 fjm, the fluctuation reached 67 fjGal.

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