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## Topband: Inverted V antenna!

 To: Topband: Inverted V antenna! W8JI@contesting.com (Tom Rauch) Tue, 7 May 2002 00:01:22 -0400
 ```> The results show that it is a BETTER VERTICAL than horizontal by 3dbi > at a elevation angle of 20 degrees to the horizon. This is off the > ends. Horizontal is broadside. Hi Don and all, I may not have expressed it as well as possible, but this is worth going over if you really want to know what polarization an antenna has. All horizontal dipole style antennas gradually tilt the radiation towards vertical off the ends. As a matter of fact, radiation off the ends is almost exclusively vertical. That's true for perfectly horizontal dipoles as well as Inverted Vee dipoles. This is so contrary to logic most of us would place a dipole's ends towards a vertical to null the vertical, when the very opposite is true! If I want to null a vertical's radiation from a dipole at the same location the deepest null in coupling occurs when the dipole is broadside to the vertical! Maximum coupling occurs off the ends of the dipole. Which begs the question, how many people with dipoles, especially those near other structures, really have horizontal polarization in the directions they think? Probably very few of us do. The actual radiation at any given point in this example is always a single polarization, but Eznec and other simple programs can not display "tilt" in the electric field. The simple display in the programs only expresses the field at two reference angles, vertical and horizontal. When we see equal vertical and horizontal components it actually represents a wave that is tilted 45-degrees, the wave is neither vertical or horizontal. Unfortunately without phase we can't tell if the wave polarization, when viewed looking towards the antenna, is in a line between lower left and upper right or upper left to lower right. Rest assured whatever tilt angle the electric field has in any given direction and angle, rotating 90 degrees from it is a perfect null, so it is a single polarization and not a mix. (Which was my point.) Now imagine the great difficulty in predicting how antennas interact with other things based on what we intuitively "feel", or what we see when we look at the antenna, or at the pattern when expressed as a ratio between two fixed reference of purely vertical and purely horizontal electric field alignment.73, Tom W8JI W8JI@contesting.com ```
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