[TowerTalk] Vertical dipoles (K4SAV)

[David J. Sourdis]

Hello,

That antenna can be improved a bit:
I would lenghten the upper loading and the vertical section to shorten the bottom radials and make  'em 
become bottom capacitive loading. Maybe the feed point will shift a little.

You get four things with this:

-Raise the current maxima from 4 meters to about 13 meters high and get a higher and bigger Ampere-degrees area. 
It is about 7% more area in this case, and about 13% (half a dB with low or no losses) if you add one meter more at the
bottom of the vertical section to make it 19 m long, starting at three meters level at the bottom instead of four meter level.

-Higher Radiation resistance, therefore, efficiency.

-The high voltage ends at the bottom will raise a bit from the ground, reducing losses, more efficiency.

-Save space to the sides and some rope from the upper part.

You will have to rename it from "1/8 wavelenght high  vertical with top loading and two radials" to "HVD with capacitive end loading"

73

David  
HK1KXA
EC5KXA

PS : Is there any common place where we can upload pics or blueprints to share and support what is written here?



> From: 7s7v at tele2.se
> To: 7s7v at tele2.se; 
> Date: Sat, 21 Nov 2009 09:37:44 +0100
 
> Try this one instead of EI7BA:
>  
> http://66.196.80.202/babelfish/translate_url_content?.intl=se&lp=ja_en&trurl=http%3a%2f%2fwww003.upp.so-net.ne.jp%2fJH1GVY%2fns-22.html

> 
 		 	   		  
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