| 摘要 |
An helical type line for travelling wave tube, with a variable diamter. The line is made on a skew surface constituted by a revolution surface on which flat surfaces have been made. The variation of the line diameter may be carried out by a variation of the revolution surface diameter, the flat surfaces being parallel to the axis of the revolution surface. That variation may be also carried out by a variation of the angle made by the flat surfaces in relation to the helix axis, the revolution surface being cylindrical. |
