As a satellite such as the International Space Station (ISS) orbits the Earth, the orientation of its transmitting antenna changes with respect to the Earth. It could have an orientation anywhere from horizontal to vertical. To get a good signal, the Earth-based receiving antenna must match the orientation of the ISS’s transmitting antenna, especially when using only a hand-held tranceiver with stock antenna. An antenna with a pair of elements placed at right angles with each other (such as a cross Yagi or a cross dipole) is best suited for satellite work, because elements at right angles can receive signals from both horizontally and vertically-oriented antennas. In this video, I have demonstrated this effect and shown how changes in antenna orientation affects the strength of the signal received.
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© Anthony Urbano (Manila, Philippines)