  We have investigated apparently stochastic fluctuations of
magnetically-supported dc discharge in cylindrical coaxial configuration. In
the system the electric field had radial direction while the magnetic field was
applied axially. The discharge vessel length was 12 centimetres. Working gas
was typically argon at pressure of several Pa, magnetic field 10-50 mT. The
contribution describes experimental results - frequency and phase analysis of
the instabilities, which we detected in our experimental system in both the
conventional and inverted magnetron configurations. We bring also 2-D PIC model
of the dc discharge under conditions, which can be achieved in the experimental
apparatus.
