I may be one of those Pete calls "those with trees conveniently situated", and
I am indeed "tempted" by this idea for a short vertical for 160M...:-)...
hardly any of my trees are more than 60 feet high. Where might I find more
specifics of the Breakall design?
73, Jerry K3BZ
----- Original Message -----
From: Tom Rauch
To: towertalk@contesting.com ; Pete Smith
Sent: Friday, June 11, 2004 8:18 AM
Subject: Re: [TowerTalk] Breakall short vertical
> Am I right to assume that although the feedpoint impedance
is 50 ohms, the
> ground loss picture is really closer to that of a single
short inverted L,
> and is established by the feedpoint impedance of a single
L rather than the
> 4 together? Any other comments on the antenna?
You are correct Pete. The ground losses are identical to a
single antenna. What you essentially have with multiple
drops is an impedance matching system. The multiple top
wires might spread the E- and H- field losses of the
horizontal wire around, and could reduce them a little bit.
I'd have to think about that a while, hi hi. Otherwise, it
is the same as a regular Inverted L the same height. You
have the same ground currents, and the same ground losses.
Multiple drops and folded elements do NOT reduce ground
losses, since the sum of currents flowing into the ground
always remains the same independent of how many drops the
antenna has for a given antenna height.
There is no such thing as a free lunch. You would need a
good ground.
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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