  The spectral distribution of spontaneous emission of electrons moving in a
plane wiggler with inhomogeneous magnetic field is calculated. We show that
electrons do complicated motion consisting of slow(strophotron) and
fast(undulator) parts. The equations of motion are averaged over fast undulator
part and we obtain equations for connected motion. It is shown, that the
account of inhomogenity of the magnetic field leads to appearance of additional
peaks in the spectral distribution of spontaneous radiation.
