Thread: Fan dipole..
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Old March 20th 07, 01:01 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Fan dipole..

"merlin-7" wrote in
:

I know that an inverted V is for the most part omni directional, but
what
about an inverted v that is only somewhat inverted? Would that not
give you a pattern more shaped like an egg?



The directivity of a half wave dipole over real ground varies with
height, and elevation angle. At the zenith it is omni directional, and at
lower elevations it has some directivity, but nothing like a dipole in
free space. Inclining the legs as in an inverted V dilutes the nulls
further and so reduces directivity, less so for large included angle.

So, the combination of an inverted V and mounting low to real ground
reduces directivity.

If you raise your dipole centre height, and decrease the included angle,
I expect that one will offset the other's effect on the pattern to some
extent.

Owen