Topband: Quarter wave sloper on crank up tower ?

[Gene Smar]

Jim:
Like Steve, I installed a 1/4 wave sloper wire for 80M off my Trylon 64-foot tower (non-crankup) at around 50-55 feet. Atop the tower I have a Bencher Skyhawk 10-element Yagi with the parasitic elements shorted to the boom with aluminum straps and hose clamps. My RF radials consist of about 7 18AWG insulated wires just below the grass, along with 125 feet or so of 2AWG wire buried 2 feet and 12 copper ground rods arranged in radials off the tower legs for lightning grounds.
I get great coverage up and down the US east coast, into the Canadian Maritime Provinces and UK and western Europe. I also shunt feed the Trylon on 160M where it works quite well for me. 
Good luck with your project. 
73 de Gene Smar AD3F 
Sent from my Radio Shack TRS-80 model 100 laptop 
 
  On Tue, May 6, 2025 at 1:34 PM, Steve Lawrence via Topband<topband at contesting.com> wrote:   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 at telus.net <jim.thom at 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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