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[TowerTalk] A4S SWR Solved-Now a new one!

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Subject: [TowerTalk] A4S SWR Solved-Now a new one!
From: kg5u@hal-pc.org (Dale L. Martin)
Date: Sat, 14 Feb 1998 23:09:03 -0600
Bill,

That's good news about your A4.  I wonder if you didn't take a
lightning hit.  I have an end segment from my driven element
which has a nice 3/8" hole burned through it.

As for the 1/4 wave half sloper (is that what it is?), I also
have one hanging from the top of the tower here.  How far down
the tower from the A4S is the feedpoint of the half-sloper?

I improved my half-sloper SWR by moving the feed point up to the
top of the pointy tower top....I mean the TOP...The coax /wire
connection is two inches from the very top of the tube....about
12" below the A3S.  SWR was 2.2:1 at 3.520 before the move and is
now 1.1:1 at 3.520.  I even had to shorten the wire after moving
it up to further reduce the SWR....which was good because the end
of the wire was 3" from the very farthest corner of my house
roof.  I sucked up over 2' of wire adjusting it for the SWR.  I
wish I had moved it up to the top of the tower long ago.

As an additional point of information, I previously had a TH6 on
the tower.  The SWR on the half-sloper at 3.520 was flat.  I
removed the TH6 after it got damaged in a hurricane and I put up
the A3.  The SWR on the half-sloper went up as a result of the
change (tophat capacitance effect, I expect) and I never could
get it down....it never occurred to me to move the half-sloper up
until recently.

73 and have fun!

Dale, kg5u
kg5u@hal-pc.org


>I'm back with good news and bad news and I don't have a clue
about the
>bad...



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