A Continuously Variable Coaxial-Line Attenuator

This paper reports on a new continuously variable coaxial-line attenuator that utilizes a center conductor of semi-insulating material. Some general design details and data are given. Specific design details for an octave bandwidth prototype attenuator are presented and discussed, and experimental results for the prototype are given. The theory on which the attenuator is based is developed and several interesting theoretical results are described.