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@tele2.se
> To: 7s7v@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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