Example of the spectra for source SPASS J134355−564917. From top to bottom: panel 1 shows the total intensity spectrum as a function of frequency. Panel 2 shows the Stokes Q/I and U/I spectra as a function of λ², with the fractional polarisation spectrum indicated by the dashed line. The fitted models for Stokes Q/I and U/I are also shown. In panels 1 and 2, the shaded regions indicate the uncertainties. Panel 3 shows the polarisation angle as a function of λ². Panel 4 shows the dirty (green dotted) and cleaned (green solid) Faraday spectrum with the Rotation Measure Spread Function (RMSF) in cyan. The black vertical line shows the peak Faraday depth.