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Comment on Which side of this dipole is ground?

JackbyDev@programming.dev ⁨1⁩ ⁨week⁩ ago

Let me rephrase (your answer may be the same). I know with some antennas there is a “ground plane” type of element that should be on the bottom. For a vertical dipole is this not the case?

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user224@lemmy.sdf.org ⁨1⁩ ⁨week⁩ ago
You do seem to be right. It should not matter in theory, but it may be better for the one connected to the center (right on this image) to be up.

For vertical polarization, in theory it does not matter which way around you orient the antenna as long as it’s vertical. However in practice, you may get slightly better results by having the element connected to the center coax conductor pointing UP.

Source: rtl-sdr.com/using-our-new-dipole-antenna-kit/

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- JackbyDev@programming.dev ⁨1⁩ ⁨week⁩ ago
  Weird that they don’t elaborate. I flipped it last night and it seemed marginally better this way, so maybe there is some truth to it. Take this with a truck load of salt as it wasn’t any sort of controlled experiment at all.
  
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  - aubeynarf@lemmynsfw.com ⁨1⁩ ⁨week⁩ ago
    in your antenna, the outside of the coax makes up a substantial part of the radiating structure. The orientation of the elements in relationship to that coax will definitely change the radiation pattern, maybe for the better maybe for the worse.
    
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    JackbyDev@programming.dev ⁨1⁩ ⁨week⁩ ago
    It has a choke on it, it’s a little blurry but you can see it. Should it be moved closer? I saw a comment on rtl-sdr’s blog suggesting it.
    
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aubeynarf@lemmynsfw.com ⁨1⁩ ⁨week⁩ ago
It does not matter. (It does not matter in a “ground plane” antenna either, the radials have nothing to do with the earth other than being easier to mount with the coax heading downward; in fact, radials should not be touching or buried in the earth as they are RF radiators and RF faces high losses in soil)

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