Tom, that gives me an idea..
An artificial tree (metallic) about 130 feet tall. Wonder how many of them I
could sell.
Where's the nearest patent office?
73,
Dale - N3BNA
________________________________
From: Tom W8JI <w8ji@w8ji.com>
To: topband@contesting.com
Sent: Sunday, August 11, 2013 10:21 PM
Subject: Re: Topband: Vertical vs inverted L question/opinions
> Why is an inverted "L" apparently so popular on 160 when it wastes so much RF
> as a cloud warmer?
"Wastes so much RF" is sort of subjective.
Comparing an L to a T, both 65 feet high and resonant over 50 radials, the T
has almost exactly the same average ground wave signal. There is only a tiny
fraction of a dB difference. In some directions the L is a tiny bit stronger,
and in some directions the T is a tiny bit stronger, but it all amounts to a
fraction of a dB.
The only real major issue is the L has about 0.4 dB front-to-back.
They aren't that much different in impedance, either.
I'm not sure anyone would see any difference, except perhaps the L fills in the
deep vertical null a little bit.
This changes if the L and T are not self-resonant. Even so, unless the L is
made so long the current maximum moves out of the vertical section, there isn't
really what most would consider a significant difference.
In my opinion, the choice is mostly a matter of what best fits the supports.
Unless you try to use Tree for an antenna, then you might be 20 dB down.
73 Tom
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Topband Reflector
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Topband Reflector
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