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antennas:start [2026/10/02 15:23] – created - external edit 127.0.0.1antennas:start [2026/10/02 16:22] (current) – Move to an individual encyclopedia article; old link redirects retained 127.0.0.1
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-====== Antennas and feed lines ====== 
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-An antenna couples a radio signal to the space around it. Its behaviour depends on frequency, geometry, installation height and nearby objects. A feed line carries energy between the radio and antenna. 
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-===== Common antenna families ===== 
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-  * **Dipole:** a balanced antenna with two conducting sections, often used as a practical starting point for HF. 
-  * **Vertical:** useful where space and installation constraints favour a vertical structure; the return-current path is part of the design. 
-  * **Directional antenna:** concentrates radiation in selected directions. A Yagi is a familiar example. 
-  * **Loop:** a closed conducting path, with many possible sizes and designs. 
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-No antenna is best for every station. Available space, bands, mounting options and the intended paths help determine a suitable design. 
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-===== Feed lines and matching ===== 
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-Coaxial cable is widely used because its shielding and routing are convenient. Balanced lines are another option. Loss, impedance, weather protection and connector quality all affect the complete system. 
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-**Standing wave ratio (SWR)** describes mismatch along a transmission line. A low SWR is useful, but it does not by itself prove that an antenna radiates efficiently. A dummy load can present a good match while intentionally converting most transmitted energy to heat. 
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-===== Documenting an installation ===== 
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-Include a diagram, dimensions, feed-line type and length, installation height, measurement method and operating conditions. Keep measured results separate from predictions and simulations. 
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-See [[wiki:article_template|the article template]] for a consistent way to document a design.