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[TowerTalk] Crossed Dipoles....

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Subject: [TowerTalk] Crossed Dipoles....
From: W8JI@contesting.com (Tom Rauch)
Date: Sat, 10 Jul 1999 09:06:13 -0400
My ASCII drawing was a little messed up. Someone sent me a 
better way to do it.

Let me try again using his style.

> If you simply parallel the dipoles at the feedpoint with no phase 
> shift, the pattern would be just like a single dipole with maximum 
> radiation at right angles to a line bisecting the in-phase wires. 
> 
> So if you have ends like this from a top view:
> 
                                                        A
                                                        I
                                                        I
                                                        I
                                X-------------------------------Z
                                                        I                       
                
                                                        I
                                                        I
                                                        B

If you feed these two dipoles so X and A (and Z and B) are in-
phase, the pattern will be a figure 8 flat on the page with the main 
lobes upper right and lower left.

If you feed these dipoles so X and B (and Z and A) are in-phase, 
the pattern will be a figure 8 with the main lobe upper left and lower 
right.

The only way you get an "omni" pattern is with a 90 degree phase 
shift at the feedpoints. Otherwise your "crossed dipole" is just a 
bow tie dipole laid flat, with a conventional dipole-like pattern.

That should be clearer I hope now that I stole a better ASCII 
drawing.
73, Tom W8JI
w8ji@contesting.com

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