Update for 11-11-21 16:45
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tech/Antenna.wiki
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tech/Antenna.wiki
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= Antenna =
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An antenna is some type of conductor, used to propogate radio signals. This is
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done because an electric current in metal induces an electromagnetic field.
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This can be transmitted and recieved by an antenna. When the antenna recieves
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the signal, an electric current is induced in the antenna due to the
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intersection of the electromagnetic radiation in a conductor.
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*Polarization* is what orientation the electric field is from an antenna. This
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is the same orientation as the conductor of the antenna. To get the best
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signal, the sending and recieving signals must be of the same polarization.
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Due to how signals propagate through the atmostphere, their polarization
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changes dramaticly, and therefore it often doesnt matter what oerientation an
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antenna has when working with signals that propogate often (such as HF, see
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[[frequency_range]]). This phenomenon is called eliptical polarization.
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@ -34,3 +34,4 @@ see [[electronics]]
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== Signals ==
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== Signals ==
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[[Propagation]]
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[[Propagation]]
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[[Antenna]]
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@ -36,3 +36,9 @@ Note
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* E skip of E,,s,, happens most duirng early summer and mid winter
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* E skip of E,,s,, happens most duirng early summer and mid winter
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- 10, 6, and 2 meters only
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- 10, 6, and 2 meters only
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- This is what makes HF so good at long distance comms
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- This is what makes HF so good at long distance comms
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* F1 and F2 combine at night, due to not being as charged
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Different parts of the ionosphere are charged at different times of the day,
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making it so comms one way but not another are possible, and making it so that
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ability to talk is limited by seasons, weather, and the sun cycle.
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