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Re: Topband: Ground loss query (re inverted L, antenna radiation resista

To: Topband@contesting.com
Subject: Re: Topband: Ground loss query (re inverted L, antenna radiation resistance, & Jerry Sevick)
From: shristov <shristov@ptt.rs>
Date: Wed, 19 Oct 2011 20:28:56 +0200
List-post: <topband@contesting.com">mailto:topband@contesting.com>
wyc <wycpublic@gmail.com> wrote:

> I did some EZNEC modeling of a planned inverted-L, and came up 
> with some results that surprised me,
...
> I then repeated the exercise with a folded-inverted-L (i.e., with twinlead).
...
> What then surprised me was the feedpoint impedance when I switched to real
> ground, and the same few radials.  Instead of going to about 87 ohms (50
> ohms ideal antenna impedance plus 37 ohms of return path resistance), it
> went to about 200 ohms.


Folding has nothing to do with either radiation resistance or ground losses.
It is impedance-transforming device only.

You've just performed 1:4 impedance transformation, nothing else.

73,

Sinisa  YT1NT, VE3EA
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