[en] Dispersion properties of slow wave lines with lumped parameters aimed for ion collective acceleration by electron rings are studied. The dependence of line characteristics on geometric parameters is followed, in particular, on the line step and screen radius. It is shown that dispersion of phase velocity and line impedance can be significantly decreased, by inserting the additional capacitive coupling. The propagating along the line pulse decay due to ohmic losses in the screen coils and capasitors is considered. The losses creen conductivity are found to be dominating. The simple analytic relations obtained permit to determine easily the basic line parameters