[en] Some investigations of noise spectra and UHF-radiations within a wide range of electron-cyclotron, electron plasma and ion plasma frequencies have been performed in ''Uragan-2'' stellarator. Threshold dependences on electrical and magnetic fields of kinetic instability excitations have been studied as well as of ion heating and disruption of quasi-stationary run-away of electrons in a plasma heated by a powerful current pulse in high magnetic fields sup(ω)ce/sup(ω)pe > 1. It was shown that near sup(ω)ce/sup(ω)pe asymptotically equals 1 the threshold character of growth of hot ion number and energy, as well as of the excitation of epithermal nonstationary electromagnetic radiations on Langmuir frequency and ion plasma frequency harmonics were connected with the ion-acoustic turbulence and the processes of nonlinear sound transformation. These effects are increased with the rise of magnetic field strength and are followed by the drop of a resistance absolute value. At the rise of electrical field strength no restrictions in injection of high ohmic power into a plasma and ion temperature rise were observed. Energy lifetime of hot ions was 40 μsec, that being one order of magnitude lower than a design neoclassical time. The results of ion heating in tokamaks were compared. (author)