The equations of motion of macroscopic quantities characterizing the nonequilibrium state of a many-particle system with a discrete energy spectrnm and subjected to the strong action of a pulsed generator are deduced by applying the Schroedinger equation for the system. Simple algorithms for the operator transformations related to impluse excitation are derived. The general properties of pulsed generators and of physical systems leading to the appearance of oscillating and stationary response signals of the excited particle system are established. As an illustration of application of the general relations, the nonequilibrium states of electron and nuclear spin systems produced by cross magneto-acoustic excitation are investigated. The prospects of developing pulse techniques for investigating electric and orbital magnetic moment systems are discussed. (auth)