Abstract: A universal cold-cathode type ion source with closed-loop electron drifting and with ion-beam propagation direction perpendicular to the plane of electron drifting is intended for uniformly treating stationary or moveable objects. Treatment procedures include cleaning, activation, polishing, thin-film coating, or etching. The ion source of the invention allows for adjusting beam parameters and configurations and has an adjustable dimensions of the ionization space between the anode and the cathode. In a preferred embodiment, the adjustment is carried out by moving the anode with respect to the cathode. The moveable anode is shifted in the direction of propagation of the ion beam or in the opposite direction, whereby the tubular ion beam is either converged or diverged. As a result, it becomes possible to adjust the surface area being treated and characteristics of the ion beam such as average energy of ions in the beam and composition of the beam, in case of a multiple-component working medium.