Electric discharge excitation modes and N<sub>2</sub> pressure range for a stable formation and maintaining of pulse glow discharge plasma in a hollow combined cathode have been investigated. It has been found that both of these parameters are influenced by the constructive peculiarities of the cathode. It has been established experimentally that the value of N<sub>2</sub> breakdown voltage for the studied construction of the cathode within the range of 50-250 Pa does not exceed -700 V.