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Antennas

X-antenna

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X-Dipole: Far-field simulations; 80m band.
(Calculations performed using EZNEC+ v5.0)

Simple dipole feed:

N and S wires driven.
E and W wires unconnected.

Model: x45dipole.ez (simulation frequency set to 3.7MHz).


Maximum low-angle radiation is broadside to the wire. Pattern can be rotated through 90° by connecting the transmitter to the E and W wires.

Shown below: slices through N-S and E-W directions. For radiation at an elevation of 45°, there is a difference of about 18dB (3 S-points) between N-S and E-W. For 80m DX working, operators and worked stations will definitely notice the difference between the two possible pattern orientations.


Splayed dipole feed:

N and E wires joined
S and W wires joined.
Model: x45splay.ez (simulation frequency set to 3.7MHz).

A more omni-directional pattern is achieved in comparison to the simple dipole configuration. Gain in the vertical direction is unaffected.



Slice through the N-S direction.

3+1 Asymmetric feed:

W, N, and E wires joined.
Model: x45_3plus1.ez .

Reduces radiation in end-on directions.



Slice through the E-W direction.

Double-T feed (Top Null):

Cancels radiation in the vertical direction.
Model: x45_2T.ez (simulation frequency set to 3.7MHz).



Slice through NE - SW

© D W Knight 2008.
David Knight asserts the right to be recognised as the author of this work.

Z Docs

Antennas

X-antenna

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