Examples of the Sun during the decay of cycle 23 for 2004–2007 (from top to bottom) at four frequencies between 432 and 150 MHz. Dates and frequencies (decreasing from left to right) are indicated in each frame. Fields of view are 2.8 R_s, intensity scales are linear, resolutions are indicated by small disks at the lower left corner of each frame. Rows are referred to as a, b, c, and d in the text (same for following figures).