The RV semiamplitudes of all known sdB binaries with spectroscopic solutions plotted against their orbital periods (see Table A.1). Binaries which were initially discovered in photometric surveys due to indicative features in their light curves (eclipses, reflection effects, ellipsoidal variations) are marked with open circles. Binaries discovered by detection of RV variation from time resolved spectroscopy are marked with filled diamonds. The dashed, dotted and solid lines mark the regions to the right where the minimum companion masses derived from the binary mass function (assuming 0.47 M_⊙ for the sdBs) exceed 0.45 M_⊙, 1.00 M_⊙ and 1.40 M_⊙. The two post-RGB objects in the sample have been excluded, because their primary masses are much lower.