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Re: Topband: Quarter wave sloper on crank up tower ?

To: "jim.thom jim.thom@telus.net" <jim.thom@telus.net>
Subject: Re: Topband: Quarter wave sloper on crank up tower ?
From: Steve Lawrence via Topband <topband@contesting.com>
Reply-to: wb6rse1@mac.com
Date: Tue, 6 May 2025 10:33:31 -0700
List-post: <mailto:topband@contesting.com>
Jim - I used a 1/4 wave sloper for 80m from the top of a 55ft 3 section crank 
up tower with a typical HF stack of antennas.The coax shield was connected to 
the tower at that point. It worked well +/- 90 degrees from the direction of 
the slope. I would not hesitate to try the same on 160m.

The sloper is long gone in favor of shunt feeding the tower. I have no radials 
either. No place for them. Just two copper ground rods at the tower base. 
(There's an article on this in QST. See my QRZ page if you're interested.)

GL - Steve WB6RSE

> On May 6, 2025, at 9:15 AM, jim.thom jim.thom@telus.net <jim.thom@telus.net> 
> wrote:
> 
> Has anybody used a 1/4 wave sloper (for 160m, aprx 120-130')  hanging from
> the top of a 89' crank up tower before ?
> Due to the 5 x sections overlapping, the feed point would have to be at the
> very top of the  tower.  IE:  it can't be part way down from the top.
> 
> Will it work with some top loading, like a 3 el  40m yagi ?   Right now, my
> modified F12 340N  yagi has all 3 x els  insulated from the boom. ( oem LL
> wire loading replaced with hb  3/8" tubing coils).    I was seriously
> thinking of bonding the REF and  DIR to the boom, to increase  the top
> loading. REF is aprx 59' long.  DIR is aprx 52' long.
> 
> I  can't shunt feed the tower, since grnd mounted radials are out of the
> question.   House is blocking the path of any radials  >  180 degs.
> 
> Jim   VE7RF
> _________________
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