Spectra of OH⁺ and H₂O⁺ (only the 607 GHz transition is shown) toward PKS 1830–211 southwest (top) and northeast (bottom) images. The hyperfine structure (hfs) for OH⁺ is indicated, with the relative strengths expected when the sublevels are populated in proportion to their statistical weights. The spectra corresponding to the strongest OH⁺ hfs component, after hfs deconvolution, are shown in dotted lines. Spectra of other species are shown for comparison.