MULTICHANNEL HETERODYNE RADIOMETER WITH COMPUTER CONTROL FOR ELECTRON-CYCLOTRON EMISSION MEASUREMENTS OF A TOKOMAK PLASMA

A multichannel heterodyne radiometer in the frequency range 50-75 GHz which has been used to measure the second-harmonic cyclotron emission of the Thor Tokomak plasma is described. Real-time frequency switching, analog output averaging, autocalibration, data-acquisition, and graphical display are all functions performed under control of an Apple II personal computer. Typical experimental results are presented to illustrate the measuring capabilities of the instrument.