Abstract:The klystron is the core component of the CINRAD / CC radar transmitter to amplify the radio frequency excitation signal, which is also the vacuum consumption devices of the microwave electric. The normal working hours of the klystron are more then 5 000 hours. The running costs and the detecting echo quality of the radar will be directly impacted by the performance degradation of the klystron. Tune tube is adjusted so that the excitation signal is sufficiently amplified and then outputs transmitter pulse that complies with the technical indicators provisions.This paper describes the replacement of the aging klystron and the adjustment method of the new klystron, which can provide technical references for the personnel engaged in radar safeguard and application, and gives a strong technical support for the maintenance of the new generation weather radar.