A friend of mine is using a 2x 160m V-beam on 40m.
The performance is as EZNEC predicted.
First he was using soft drawn copper magnet wire which he pre stretched.
Stretching was not the problem as he easily could retune but sag was.
With that much sag the antenna was not working as expected.
He then used 1.2mm diameter MIG welding wire (Alumig Mg4.5MnSAl)which sags
only very little and now the antenna is working fine for some years.
Those welding wires are available in several different sizes.
My 140m long beverage hung between two trees and made of 0.8mm diameter of
that stuff is now up for 7 years and never stretched, sag is just 50cm as
most.
73
Peter
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of dw
Sent: Dienstag, 15. September 2015 22:30
To: towertalk@contesting.com
Subject: Re: [TowerTalk] [NCCC] Has anyone every put up a V-beam?
Hi John,
You can check out these web-sites:
http://www.w8ji.com/rhombic_antennas.htm
http://www.vk5sw.com/Vee%20Beam.htm
In my case it will be ultra simple.
I will pull a line up into a tall tree for the center feed-point.
I use home-made center pieces made out of sturdy plexi-glass.
I'll feed it with ladder-line coming down to the ground, probably 45-50
feet.
I'll attach the ladder-line to a homemade L-network on the ground, and a
long stretch of RG-213 to the house.
Mine will be favoring west/east, so I'll walk west 219 feet from the
feed-point and put a marker there.
Then measure 90 feet north (perpendicular) to establish the northern leg
end-point.
And measure 90 feet south (perpendicular) to establish the southern leg
end-point.
So the two outer legs will be 180' apart.
Throw up ropes over trees to get both legs up as high as I can get them.
Preset the L-network to the cw portion of 40m.
Fingers crossed it performs as EZNEC indicates.
Fun stuff!! :-]
Duane
On Tue, Sep 15, 2015, at 01:05 PM, John Litz, NZ6Q wrote:
> Where r plans for this would love to try in Merced for CQP
>
> John nz6q
>
> Sent from my iPhone
>
> > On Sep 15, 2015, at 3:33 PM, Mike Fahmie via NCCC <nccc@contesting.com>
wrote:
> >
> > I've used a 6 wavelength 20M V-beam @ 60' with a Johnson Matchbox on
Field Day a few times, it was a blast, owned the channel! Totally
outperformed the 3 element Yagi.
> > From California, I pointed it toward the center of the Eastern Seaboard.
> > -Mike-
> > WA6ZTY
> > From: dw <bw_dw@fastmail.fm>
> > To: "towertalk@contesting.com" <towertalk@contesting.com>
> > Sent: Tuesday, September 15, 2015 12:26 PM
> > Subject: [TowerTalk] Has anyone every put up a V-beam?
> >
> > Hi all,
> > I think I have the space to do this, although the property is heavily
> > wooded with oak trees.
> > I've modeled a V-beam with 219 feet legs for 40 meters.
> > Eznec is showing a gain of about 10dbi.
> > I'm wondering if anyone in the group has experience with this type of
> > antenna?
> > If so, what did you think about it?
> > Tnx
> > N1BBR
> > --
> > Bw_dw@fastmail.net
> >
> >
> >
> >
> > _______________________________________________
> >
> >
> >
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> >
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--
Bw_dw@fastmail.net
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