NONLINEAR DIAGNOSTICS, ACOUSTIC WEIGHING, ANDREEV’S HAMMER AND PROBE MICROSCOPES
A method of nonlinear diagnostics based on “acoustic weighing” of sheet materials is discussed. The defect mass or mass deficit determines the frequency shift of the vibrating membrane. The measuring device is described made by academician N.N. Andreev in 1925 and based on the effect of “rattling” due to the “bouncing” of a small load lying on the telephone membrane. The harmonics of oscillations that appear at sufficiently large amplitudes of oscillations are calculated. It is shown that harmonics can also appear during the operation of modern high-precision instruments, for example, tunneling and atomic force microscopes.