Decimetric-metric radio emission during the impulsive phase of the 2021 August 24 event. Panel (a): Dynamic spectrum (ORFEES, 0.1 s; Glasgow e-Callisto station, 0.25 s resolution). Dark shading indicates bright emission. Panels (b and c): NRH maps (iso-intensity contours superposed on an image) of the first J burst (b; 11:58:00 UT) and the last type III burst (panel c; 12:00:19 UT). The contours delineate the half-maximum level at the burst peak (0.25 s resolution); the different colours represent different frequencies (see legend at right). The set of tilted ellipses in the upper right corner shows the half-maximum levels of the nominal interferometric antenna beam. Solar north is at the top, east on the left. The white arc shows the optical solar limb.