Gary Slagel wrote:
> Hi guys,
>
> I tried to model a v shaped dipole yesterday and was surprised by the
> results. I'm looking at a dipole with the ends bent back toward each
> other rather then an inverted vee. I started with a straight dipole,
> then bent the ends toward each other so they enclosed a 135 degree
> angle, then bent them to enclose a 90 degree angle, and last a 45
> degree angle.
>
> The azimuth pattern I got was identical for each configuration. The
> direction was different depending on how I rotated the wire to change
> the angle, but the pattern was identical.
>
> Does this seem reasonable or was I making an error or does eznec have
> a problem modeling this? I was using the free eznec provided with
> the arrl antenna book.
>
>
the entire antenna is all in a flat plane? so it's looking sort of like
a big "C"
Most of the pattern is determined by the middle of the dipole, so
bending the ends doesn't do much other than change the feedpoint
impedance. a half length (1/4 wavelength long overall) dipole with
capacity hats to make it resonant has almost exactly the same pattern as
a full sized dipole.
In fact, an idealized dipole has about 2.2 dBi gain, while an
infintesimally small dipole (called a Hertzian dipole) has a gain of
about 1.7 dBi.. unless you plot the two patterns on top of each other,
you wouldn't notice the difference.
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