Here is K1EA's description of his
self supporting 80M Verticals,
presented with his permission.
de Tom N4KG
--------- Forwarded message ----------
From: "Ken Wolff" <kwolff@ultranet.com>
To: <n4kg@juno.com>
To: <towertalk@contesting.com>
Date: Thu, 11 Jan 2001 12:22:47 -0500
Subject: RE: [TowerTalk] 80 Meter Self Supporting Vertical.......
Hi Tom,
The element fits into a top section of Rohn 45 with a rotor plate mounted
two rungs down.
I had a machine shop put 5 inch holes in the top plate and rotor plate.
Then
I had some "shoulder washers" machined out of 1 inch lexan. The inner
hole
is 4" for the element and the outer ring of the shoulder is 5" to fit the
top plate. Thus, there is a 1/2" ring of insulator between the element
and
top plate.
One interesting thing: We sometimes get nor'easters and hurricanes that
start with the wind out of the east, then rotate through north and on to
west as the storm passes to the east of us. Because the element is bowed
over the entire time, the bottom of the element rotate in the shoulder
washer and sometimes breaks off the feed wire!
This is something I didn't anticipate, and it made me laugh when I
realized
what happened the first time.
I built this four square after Jim Breakalls's talk about raised radial
systems at Dayton (1987). The bases are two sections of Rohn 45 in a yard
of
concrete. The elevated radials are at about 15'. My first contact was a
long
path JA two days before CQWW CW, so I decided to keep it.
There are 700 pounds of aluminum and 8 sections of Rohn 45 in this
antenna,
so it wasn't cheap.
- Ken
-----Original Message-----
From: n4kg@juno.com [mailto:n4kg@juno.com]
Sent: Thursday, January 11, 2001 5:57 AM
To: kwolff@ultranet.com
Subject: Re: [TowerTalk] 80 Meter Self Supporting Vertical.......
Hi Ken,
Long time no hear! Thanks for the contribution to TT.
Two questions:
What do you use for a base insulator?
How is your base configured?
(How deep? what material?)
73, Tom N4KG
On Wed, 10 Jan 2001 "Ken Wolff" <kwolff@ultranet.com> writes:
> My self supporting 80 mtr verticals are still going strong after 13
> years. Of course, they start with 4 inch OD 1/4 inch wall tubing
> and taper down to 3/4 inch!
>
> Ken K1EA
>
> -----Original Message-----
> From: owner-towertalk@contesting.com
> [mailto:owner-towertalk@contesting.com]
> On Behalf Of n4kg@juno.com
> Sent: Wednesday, January 10, 2001 11:06 AM
> To: TOWERTALK@contesting.com
> Subject: Re: [TowerTalk] 80 Meter Self Supporting
> Vertical.......
>
> A truly self supporting 80M vertical is a challenge.
>
> A set of LIGHT guys, close in, greatly simplifies the
> design. For relatively short masts with very small
> loads, there is no reason the guys can't be spaced
> very close to the mast, say 30% of the height, as
> long as the vertical load does not exceed the rating
> of the material. Low stretch black ropes and some
> small screw anchors should do the job and be
> nearly invisible from a distance.
>
> de Tom N4KG
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