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In this paper I first address the question of whether the seat of the powerradiated by an antenna made of conducting members is distributed over the``arms'' of the antenna according to -J . E, where J is the specified currentdensity and E is the electric field produced by that source. Poynting's theorempermits only a global identification of the total input power, usually from alocalized generator, with the total power radiated to infinity, not a localcorrespondence of -J . E dv with some specific radiated power, r^2 S . n dO. Ithen describe a model antenna consisting of two perfectly conductinghemispheres of radius a separated by a small equatorial gap across which occursthe driving oscillatory electric field. The fields and surface current aredetermined by solution of the boundary value problem. In contrast to the firstapproach (not a boundary value problem), the tangential electric field vanisheson the metallic surface. There is no radial Poynting vector normal to thesurface. Numerical examples are shown to illustrate how the energy flows fromthe input region of the gap and is guided near the antenna by its ``arms''until it is launched at larger r/a into the radiation pattern determined by thevalue of ka.Comment: 24pages, 8 figures, submitted for publicatio

How an antenna launches its input power into radiation: The pattern of the Poynting vector at and near an antenna