Phase pushing measurements of a four-cavity multiple-beam klystron

Summary form only given. The phase sensitivity of a high power amplifier to fluctuations in operational parameters such as power supply voltage is an important characteristic for applications in advanced radar. We present the results of experimental measurements of the phase sensitivity (pushing factor) of a four-cavity multiple-beam klystron (MBK) operating in S-band. This MBK has recently been shown to generate ~600 kW peak RF power with an electronic efficiency of 40% and a 3-dB instantaneous bandwidth of ~2% at a center frequency of ~3.3 GHz. The nominal operating parameters of the eight-beam electron gun are 45 kV, 32 A (8times4 A). The measured pushing factor is in the range of 0.0134deg/volt to 0.015deg/volt and is in excellent agreement with analytic theory and large-signal simulation. We will discuss the experimental results, describe the measurement technique, and discuss the analytic model and simulations