Withdrawn Standard. Withdrawn Date: Dec 03, 1992. No longer endorsed by the IEEE. It has been recognized that a standard was needed for planar transmission lines, which are an important transmission medium in hybrid and monolithic circuits. The purpose of this standard is to provide a uniform basis of understanding, communication, and definition to benefit those engaged in the use and design of planar transmission lines. The standard provides definitions of the planar transmission line configurations and also their physical and electrical characteristics.