  In the framework of a QCD inspired relativistic potential model, we evaluate
radiative decay rates of heavy mesons and their coupling with soft pions. The
agreement with the existing experimental data is satisfactory. In the limit
$m_Q \to \infty$ one obtains results in agreement with the Heavy Quark
Effective Theory and is able to predict the values of the relevant couplings;
in particular, for the scaled $B^*B \pi$ strong coupling constant $g$, we find
that the non relativistic constituent quark model prediction $g=1$ is modified,
by the inclusion of the relativistic effects due to the light quarks, to the
value $g=1/3$, in agreement with recent QCD sum rules determination.
