Travelling wave tube with delay line

摘要

The tube is formed by having a stack of pole shoe rings (P) of soft iron that alternate with intermediate rings (Z) of such as copper and are bonded together. The central hole provides a location for the delay line coil. Locating grooves are cut at 120 deg. spacings by a wire erosion process and into these are inserted retaining bars of insulating material. The arrangement provides focussing.