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Low-power plasma generators with two kinds of hot anode/nozzle structures, one with a natural radiation-cooled nozzle and the other with a regeneratively cooled nozzle, were designed to investigate the dependence of the volt-ampere characteristics on the anode temperature. Pure argon, nitrogen or hydrogen gas was used as the plasma working gas at input powers from 130 to 1200W in a plenum chamber kept at a pressure of below 20 Pa. Variations of the arc voltage with changes in arc current, gas flow rate and firing time (anode temperature) were examined, and the effects of the arc volt-ampere characteristics on the properties of the ejected plasma flow from the nozzle exit are discussed with respect to the evaluation of the average plume temperature and flow velocity. Results show that there are definitely non-negligible effects of anode temperature on these characteristics. [ABSTRACT FROM AUTHOR]