VLA 7 GHz maps of HCG15 at 20 arcsec resolution, before (left and after (right) subtracting the discrete radio sources associated with the group. The left-hand panel shows the VLA-D observations only, whereas the right-hand panel shows the combined VLA-C+D dataset. Contours start at 3σ and scale by a factor of $\sqrt{2}$, where σ values are reported in Table 3. Colourmaps range from −1σ to 300σ on an arcsinh stretch to emphasise faint emission, although we note that no significant diffuse emission is detected.