A four loop helix radiates at 94.28 MHz. The loop length is 1.591 m, exactly one half the operating wavelength 3.182 m. The 4 loop helix is imaged to simulate a two loop helix over a ground plane (the y_z plane). The current along the helix, including image radiators, is animated as point sources. The continuous distribution of current along the helix is charted, showing a current null at the feed point. The input impedance of the helix is thus computed to be very large. dA is positioned on the y_z plane where, by image considerations, the tangent electric field must be zero. This is verified in the animation. The operating wavelength of the system is changed to 100 m to show the radiation pattern in the low frequency limit. dA is moved to the x_y plane to show the anti-symmetric magnetic field in the low frequency limit. Also shown in this limit is the current distribution, and the Poynting field, essentially that of a dipole. dL is positioned to animate electromagnetic field along the helix axis.
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