Spectral index profiles along the jet propagation lines of 4C 70.19. Top: Profiles measured in the spectral index map between 145 and 4850 MHz (left panel of Fig. 18). The plot is limited to 3′ from the core to better present the inner parts of the jets. Bottom: Profiles as in the upper panel, but along the entire propagation path. In both panels the vertical dashed line marks the optical D₂₅ luminosity limit of the host galaxy NGC 6048 and the main turning points of the jets are marked with crosses and labelled in corresponding colour.