Abstract:In order to solve the problems of hidden focusing coil faults and complex diagnosis of klystron faults.Based on analyzing the design principle of klystron and focusing coil,this paper combines the composition diagram of the CINRAD/SB new generation weather radar klystron and focusing coil.By analyzing the index parameters and waveform of key components and key points,measured parameters and waveforms,adjusting the key components and key point parameters and waveform to judge the situation of the klystron and its peripheral components.The high voltage inaccurate and no return wave fault caused by CINRAD/SB radar klystron and focusing coil are successfully analyzed,located and eliminated.