The two-stage mechanical oscillator is an invention of academician Veljko Milković which made him famous in the scientific world. This super-efficient mechanism has the possibility of various applications, the most interesting of which is the production of electricity. Research on a two-stage mechanical oscillator is represented on all continents, of which India leads in the number of scientific papers published on the topic of this mechanism.
The goal of this work is to demonstrate a benefit of investing energy in accordance with gravitation in the two-stage mechanical oscillator in the case of greater amplitudes of a physical pendulum interacting with a lever. New facts with the samples and explanations are removing any doubt about the validity of previous measurements and along with some additional clarifications confirm ultra efficiency of the device.