At the Flerov Laboratory of Nuclear Reaction in Dubna, an ECR-ion sour
ce DECRIS-14 (Dubna Electron Cyclotron Resonance Ion Source) is being
built on the 14.5 GHz klystron. The main features of the source vacuum
system, which is based on the turbomolecular pumps VMN-500 (Russia),
are described. The influence of the magnetic field leakage from the so
urce on the work stability of the turbomolecular pumps is also given.