The design of the input and output transformer for wide-band helix TWT

The paper presents a design method for the input and output transformer placed inside the helix of a wide-band helix TWT. The transformer uses a two vane asymmetrically arrayed vane-loaded helix line to match the general helix line and the input and output connector. Because most or all of the transformer can be built inside the helix, the input and output devices of the TWT are smaller than before. The wide-band matching properties of the transformer are the same or better than the transformer consisting of all coaxial parts.