  Temperature dependences of thermoelectric power S(T) at $T>T_c$ of the
Hg-based high temperature superconductors
Hg$_{1-x}$R$_x$Ba$_2$Ca$_2$Cu$_3$O$_{8+\delta}$ (R=Re, Pb) have been analyzed
with accounting for strong scattering of charge carriers. Transformation of
parameters of a narrow conducting band in the region of the Fermi level was
studied. The existence of correlation between the effective bandwidth and the
temperature of a superconductive transition $T_c$ is shown.
