Single pulses calculated for the beam types shown in grey at the top of Fig. 3. The figure shows several classical single pulse effects: left-right-middle modulation with core pulses (top left), jump by half of the modulation phase, with sporadic nulls in pulses 2 and 19 (top right), pulsation mode change at intermodal nulling (bottom left), and interior drift of sub-pulses flanked by fixed-longitude flux modulations (bottom right). The corresponding partial profiles are shown on top with a line and the average profiles for 2000 pulses in grey. Parameter values are (from left to right, top to bottom) P_d = 2.9, 4.2, 2.8, 1.9, β′= − 0.1, 0.1, 0, 0.4, everywhere, everywhere, and , except for the top right, where ; thus, only the top-right panel is for the symmetric beam (Fig. 3, top right).