Radio spectrum of Tycho, including measurements from this work (in blue). The green line corresponds to the power-law spectral index (PL SPX) of 0.58 reported in Green (2017), and the yellow line is the best-fit (BF) power-law spectral index from these data points. The literature (lit) values in red are taken from: Klein et al. (1979), Green et al. (1975), Hurley-Walker et al. (2009), Katz-Stone et al. (2000), Kothes et al. (2006), Planck Collaboration et al. (2016), Gao et al. (2011), Langston et al. (2000), Williams et al. (1966), Scott & Shakeshaft (1971), Artyukh et al. (1969), Bennett (1963), Fanti et al. (1974), Conway et al. (1965), Kellermann et al. (1969), and Horton et al. (1969).