[TowerTalk] FW: Vertical Dipoles
David J. Sourdis
hk1kxa at hotmail.com
Wed Nov 18 09:54:32 PST 2009
Here you can find the file list.
"The pertinent statement is that a monopole has twice the power density
of a dipole. "....this gives a directivity or gain of the monopole
antenna that is twice that for the double-length dipole."
I am not an expert but I think that power density is the same, just that one half is gone to the radials.
As I understand the lower third (0º to 30º) of a 90 degree (quarter wave) monopole has the same current-degree area as the top two thirds (30º to 90º)
So, also, the center third of a dipole has the same Amperes-degree as a whole 90 degree monopole or the same as the rest of the dipole, the outer thirds.
If I use a HVD thas has a vertical section 60º and the rest is end loading, capacitive, coil, etc, has the same current area as a full sized quarter wave monopole.
> Date: Wed, 18 Nov 2009 10:14:41 -0600
> From: ranchorobbo at gmail.com
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] Vertical Dipoles
> I don't think there is any relevance in comparing an inverted V to a
> vertical dipole.
> More important is the comparison between vertical monopoles and
> vertical dipoles. See this paper by Gandhi, Lazzi and Furse. Note
> especially the paragraph following equation 1:
> http://www.ece.utah.edu/~ece3300/Labs/lab3/MONOPOLE ANTENNAS.pdf
> The pertinent statement is that a monopole has twice the power density
> of a dipole. "....this gives a directivity or gain of the monopole
> antenna that is twice that for the double-length dipole."
> It is also important to go to the end of the paper and study the
> figures and plots.
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> TowerTalk at contesting.com
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