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Topband: Improve efficiency?

To: topband@contesting.com
Subject: Topband: Improve efficiency?
From: Lew Sayre <w7ew@arrl.net>
Date: Mon, 2 Nov 2009 22:41:06 -0800
List-post: <topband@contesting.com">mailto:topband@contesting.com>
TopBanders,
    While trying to attract SV3RF's attention last night on Top band it
occurred to me that I need more efficiency in my Tx system.
What I have is two fir trees, each about 110' tall and 189' apart. I have 2
12GA copper stranded wires going up and over the top of
each tree with about 18' of wire going from vertical to horozontal as it
goes over the top.  I have 60 1/4 wave radials under each wire
on the rocky ground that runs through essentially forest which surrounds
these two trees with a bunch of other fir trees. I layed down
radials under each wire until I saw no further change in the SWR in each
vertical wire.  The SWR individually for each wire is about 1:1.5 at 1830
so I've used no matching system.
    I have a COMTEK Box that I use where I do see some F/B when working
Oceania and EU...but not much..pretty subjective when the max gain might be
3 dB.
    I also suspect that all the fool trees around me knock down the signal
some...but no real idea of how much.
Question: You think changing from the inverted L configuration to an angled
wire at about 60 degrees for the full 128' length would make any improvement
in efficiency?  Would angling the wire toward EU help or hurt the signal in
that direction?
     When the tower fairy comes some day and erects a 190' tower in my
woods, then maybe I can make a K3LR type array..but until then any
suggestions for the current lash-up to make it radiate better?
    73 and I remain,
    Lew   W7EW/W7AT
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M

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