Improvements on a Device for Plotting Electrostatic Probe Characteristics in Variable Plasmas

Langmuir-probe and double-probe characteristics corresponding to time-varying plasma properties can be displayed instant by instant on the screen of an oscillosope, provided the variation is periodical or at least meets certain requirements of reproducibility. The technique used, essentially an electronic stroboscope, has been described elsewhere under the name "plasmograph." The aim of this paper is to describe several recent improvements of this technique.