  The black hole model with a self-gravitating charged spherical symmetric dust
thin shell as a source is considered. The Schroedinger-type equation for such a
model is derived. This equation appeared to be a finite differences equation. A
theory of such an equation is developed and general solution is found and
investigated in details. The discrete spectrum of the bound state energy levels
is obtained. All the eigenvalues appeared to be infinitely degenerate. The
ground state wave functions are evaluated explicitly. The quantum black hole
states are selected and investigated. It is shown that the obtained black hole
mass spectrum is compatible with the existence of Hawking's radiation in the
limit of low temperatures both for large and nearly extreme Reissner-Nordstrom
black holes. The above mentioned infinite degeneracy of the mass (energy)
eigenvalues may appeared helpful in resolving the well known information
paradox in the black hole physics.
