The dependence of the intensity of the bremsstrahlung and the characteristic X-radiation induced by a beta-emitting14C-isotope was investigated as a function of the layer thickness and the atomic number of the absorbent. The theoretically calculated and measured values of layer thickness required for maximum radiation intensity were in good agreement. The atomic number values required for maximum bremsstrahlung and characteristic radiation were ascertained. The obtained extreme values were attributed to a resonance effect occurring by the interaction of β-particles with theK electrons of the absorbent.