Best-fitting profiles for NGC 891 UM (top panel), NGC 4013 UL (middle panel), and NGC 4631 UM (bottom panel). For each galaxy, SPINNAKER fits the LOFAR HBA (top graph) and L-band (middle graph) intensity profiles as well as the SPIX profile (bottom graph) simultaneously. The model is shown as a red line. The advection model is applied to NGC 891 and NGC 4631, while the presented strip of NGC 4013 is fitted with a diffusion model.