A parabolic receive dish of diameter 32 m and focal length 12 m is illuminated by a distant source at 1000 m radiating at 150 MHz. The source is circularly polarized in the y and z planes. The dish focus is placed at the origin. dL is positioned to animate the electromagnetic field at the dish focus. The circular currents induced on the dish are animated and shown graphically. Also shown are the tangent and bi-tangent surface vectors across the dish. Surface currents (x,y,z components) are computed. The distant radiator is animated in the y_z plane. The source is translated 100 m in the y direction, and linearly polarized in y direction, to illuminate obliquely a flat disk. The Poynting field with oblique illumination is charted, and dA is positioned to animate radiation reflected obliquely off the dish. Incident linearly polarized electric field at the disk surface is decomposed into TE and TM components for computation of disk surface currents, which serve as secondary source. These currents , mostly in y direction, are animated.
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