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Old April 18th 06, 10:21 PM posted to rec.radio.shortwave
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Default Horizontal, Vertical and Sloping Dipole Antennas [Was : Why Tilt ? - The Terminated Tilted Folded Dipole (TTFD / T2FD) Antenna]

Dale [W4OP],

Horizontal, Vertical and Sloping Dipole Antennas
http://groups.yahoo.com/group/Shortw...a/message/9090


HORIZONTAL DIPOLE ANTENNA :
A basic Horizontal 1/2 WL Dipole Antenna that is Flat
with the Center mounted at 1/4 WL above-the-ground
and existing in a plane parallel to the ground; can be
said to Radiate mostly Off-the-Sides and not the ends.
This Horizontal Dipole Antenna has a predictable
Take-Off-Angle.

- - - The Surface of the Ground acts as a Reflector causing
the majority of the Signal to go Up and Off-the-Sides of
the Wire Antenna Element in a Horizontal plane : Making
the Horizontal Dipole Antenna mostly a Upwardly Radiating
Bi-Directional Antenna.


VERTICAL DIPOLE ANTENNA :
Conversely a basic Vertical 1/2 WL Dipole Antenna that
is Straight-Up-and-Down with the Center mounted at 1/4
WL above-the-ground and existing in a plane perpendicular
to the ground; can be said to Radiate Equally-All-Around;
but not off the ends. Again this Vertical Dipole Antenna
has a predictable Take-Off-Angle.

- - - Again the Surface of the Ground acts as a Reflector
and the majority of the Signal to go Up and Equally Around
(Still Off-the-Sides) the Wire Antenna Element in a
Horizontal plane : Making the Vertical Dipole Antenna an
Upwardly and Outwardly Radiating Omni-Directional Antenna.


30 DEGREE SLOPING {SLANTED} DIPOLE ANTENNA :
So we come to a 30 Degree Sloping Dipole Antenna that
is Slanted at an Angle Off-the-Horizontal {Vertical?} with
the Center mounted at 1/4 WL above-the-ground. Here the
majority of the Signal can be said to Radiate Off-the-Sides
but a portion of the Signal will Radiate Equally-All-Around;
but still not off the ends. As you point-out the Take-Off-Angle
would be closer to the Horizontal [Flat] Dipole Antenna.

NOTE - The lower Tip of this Slanted Dipole Antenna is
3/16 WL above the ground and the upper Tip is 5/16 WL
above-the-ground and the Vertical Dimension of the 30
Degree Sloping Dipole Antenna is 1/8 WL which makes
it effectively a 1/8 WL Vertical Radiator.

- - - Again the Surface of the Ground acts as a Reflector
and the majority of the Signal will go Up and Off-the-Sides
of the Wire Antenna Element in a Horizontal plane; however
some of the Signal does radiate in-all-directions in the
Horizontal plane : Making the 30 Degree Sloping {Slanted}
Dipole Antenna less of a bi-directional Antenna and more
of an omni-directional {semi-omni} Antenna.

Well that is the way that I 'envision' the Radiation properties
of the 30 Degree Sloping Dipole Antenna in my-minds-eye 8;-}

T2FD / TTFD ANTENNA :
Back to Why "Tilt" the Terminated Tilted Folded Dipole (TTFD /
T2FD) Antennas - - - The above rational is my simple understanding
of One-of-the-Whys for the 'tilting' of the Terminated Tilted Folded
Dipole (TTFD / T2FD) Antennas. To help slightly improve the
Omni-Directional characteristics of the basic Dipole Antenna in
this more Broad Banded design and application.

Oops ! - IIRC - FWIW - I am frequently right . . .
except when I am wrong, Wrong. WRONG !
{ Please Educate and Enlighten Me - Should I Be :-}


very little science coupled with mostly common sense - iane ~ RHF
[ Keeping It Simple ad Practical = KISAP :]