We study the regularity of convolution powers for measures supported on Salem sets, and
prove related results on Fourier restriction and Fourier multipliers. In particular we show that for
$\alpha $ of the form $d\,/\,n,\,n\,=\,2,3,...$ there exist $\alpha $-Salem measures for which the ${{L}^{2}}$ Fourier restriction theorem holds in the range $p\,\le \,\frac{2d}{2d\,-\,\alpha }$. The results rely on ideas of Körner. We extend some of his constructions to obtain upper regular $\alpha $-Salem measures, with sharp regularity results for $n$-fold
convolutions for all $n\,\in \,\mathbb{N}$.