The fraction of daughter nuclei that recoil out of the catcher foil after-alpha-decay of mass-separator implanted mother nuclei is determined experimentally and compared with calculations. The correction that has to be applied on the alpha-branching ratio, obtained by comparing the mother and daughter activity in one-alpha-detector, is at least 20%. Previously published branching ratios can be wrong due to the underestimation of the correction procedure. As an example, the Rn-202 --> Po-198 --> Pb-194 decay chain is studied.