Gary Slagel wrote:
> I didn't do a very good job of describing the antenna. I'm not really
> folding the ends back into a C. I'm making a flat V.... like an inverted
> Vee but with the ends horizontal rather then drooping to the ground.
>
> I didn't expect much effect as I brought them back to enclose a 135 degree
> Vee but I was surprised that when the Vee was enclosing only a 45 degree
> angle, EZNEC still showed it with an identical pattern to a broadside dipole.
> So... if the pictures I drew below are understandable, I wouldn't have
> thought these two dipoles would have an identical azimuthal pattern!
>
> ----------------o o---------------- broadside dipole viewed from above
>
> o o 45 degree vee dipole viewed from above
> / \
> / \
> / \
>
Oh yeah.. the pattern will be almost identical.. The "phase center" of
the bent dipole is about 1/4 to 1/3 of the way from apex to tails,
depending on the angle.
Think of the far field as being the sum of the fields from a bunch of
little chunks along the antenna. When you bend it, the direction of
current is slightly different, but since it's matched on the other side,
the "off center-ness" cancels. So now, all you've really got is the
same as if you had a sort of stepped dipole (with magic non radiating
interconects):
o o
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