Experimental study of broadband output circuit of rectangula π-TM310 mode double-gap cavity loaded by coaxial line filter

The process of experimental study of a broadband output circuit of rectangular π-TM310 mode double-gap cavity loaded by coaxial line filter is introduced. Meliorative structure and some improved measures aiming at the main technical difficulties are taken to obtain reliable experimental results. The tested data show that the rectangular π-TM310 mode double-gap cavity couples with the output coaxial line moderately, the external quality factor is about 30, and the characteristic impedances along different beam holes remain uniform. The broadband output circuit of rectangular π-TM310 mode double-gap cavity loaded by coaxial line filter has a relatively wide band, the bandwidth in X band reaches 800 MHz, and the phase delay is linear with frequency. These tested data are consistent with simulation result and confirm the conclusions of theoretical researches. The results of this experimental study demonstrate that the broadband output circuit of rectangular π-TM310 mode double-gap cavity loaded by coaxial line filter will be favorable to upgrading efficiency and bandwidth of X band high-power multi-beam klystrons, and the application to the practical development engineering is feasible.