Design and investigation of high-power helix TWT for systems of distant and space communication

The application in output cascades of multichannel high-power transmitters of wideband vacuum devices, which are capable to work at several frequencies simultaneously, is an actual problem. The multifrequency modes were investigated in high-power helical TWT, having the band of amplified frequencies more than 40% and working without regulation of applied voltage in all operating frequency range. The third-order elements of the intermodulation products (3rd IMPE) were investigated by operation in a multifrequency mode at different levels of the output signal. For the purpose of getting a regular amplitude-frequency characteristic (AFC) and damping of self-excitation in a working mode, we used different parameters of the helix for the different parts of a slow-wave system (SWS) and optimum location of additional local attenuators