The present communication reports experimental verification of one of the existing generating mechanisms of convectively generated gravity waves (CGW), viz., mechanical oscillator effect. Two deep convective systems are chosen for the present study. Continuous observations of vertical velocities provided an opportunity to study the spectra of CGW above the deep convection using wavelet analysis. Mechanical oscillator effect is examined by observing the oscillations of the vertical velocities in the mid troposphere. The present analysis showed time localized mid tropospheric peak vertical velocity oscillations at two distinct time periods. The resultant oscillation due to the interaction of these two oscillations is observed in the lower stratosphere, which is an exciting result from the present study. As there are very few observational evidences in support of mechanical oscillator effect, the present results are of importance for gravity wave community.