ALFALFA and WSRT data for AGC 198606. Top, left: spectra for the source: solid purple is the ALFALFA spectrum, dashed blue-purple the 210′′ WSRT spectrum, dotted blue the 105′′ WSRT spectrum, and the dashed-dotted green the 60′′ WSRT spectrum. The light dotted black lines indicate the velocity range used for creation of the WSRT moment maps. The bottom panel shows the noise from a representative region of the WSRT data cube. Top, right: the ALFALFA total intensity H i map in grayscale with the region used for source measurement highlighted by the dashed rectangle. The yellow contours are the WSRT 210′′ moment zero map contours starting from 2 × rms and increasing by ; dashed negative contours with the same spacing are also shown. The blue ellipse represents the ALFALFA fitted ellipse and the dashed blue circle the equivalent , average angular size. The dotted green circle represents the effective half-flux aperture derived in this work. Bottom: the WSRT H i data. From left to right, the panels show the velocity field with column density contours overlaid (and the mask used to extract the integrated flux density and spectrum in dark gray), the velocity dispersion map with lines of constant velocity from the velocity field, and a position velocity slice along the arrow shown in the left and central panels. The H i column density contours for the three resolutions are [0.7,1, 2, 3, 4 ] × 10¹⁹, [1, 2, 3, 4, 5 ] × 10¹⁹ and [3, 4, 5, 6 ] × 10¹⁹ atoms cm^-2. The constant velocity contours are [42, 46, 50, 54, 60] km s^-1. Contours for the position-velocity slice start at 2 × rms of the data cube and increase by ; negative contours with the same spacing are also shown.