As an update, a 2x4 cut to a hexagonal block can be drilled for 48" 1/2" dowels
to carry the corners of this antenna. Put an angle bracket on hub for mast.
I tie monofilament loops at the corners of the
folded element to fit in a slotted end of the dowel. Then the T end of driven
element
dipole can have mono extensions to reach corners. When loops are inserted, the
thing
draws up into a bow, about 6 -8" elevated over hub. Put a 4 turn 3" coil in
end of
coax--RG-316--as choke. I'm not worried about 1/2 dB extra loss in thin teflon
coax at
20 feet length, considering the advantage of low weight, easy storage--it all
bundles up
to 4 feet plus hub with the elements and coax in a gallon zip bag.
My favorite 6m antenna--even at home. Did find that the dowels, although
convenient,
are a bit more brittle in tree encounters. But very easy and
cheap to replace if you carry a spare pair.
David AB2YI
On Aug 4, 2011, at 3:51 PM, Eric Smith wrote:
> "As advertised" 10dB gain, 20dB f/b... and certainly fits the "easy build and
> set-up" considerations... and with the right materials used can make an
> extremely durable antenna or "build it out of junk"... It is inherently a
> strong antenna mechanically...
>
> Certainly worthy of consideration... Might want to set up a "range" and
> measure the gain:)
>
> Eric
> KB7DQH
>
> --- dm5957@gmail.com wrote:
>
> From: David Muller <dm5957@gmail.com>
> To: VHFcontesting@contesting.com
> Subject: Re: [VHFcontesting] Design for a 6M Rover Yagi...
> Date: Wed, 3 Aug 2011 15:55:19 -0400
>
> I found that supporting the Mini Horse antenna designed by SM0DTK
> http://hem.passagen.se/sm0dtk/
> on two crossed and bowed 8-foot wood strips, set in plywood blocks,
> I could fit the folded wire 6 meter, 3 el beam in a 4' x 7' rectangle--just
> fine for roving.
> That's only a little deeper than the Moxon I have used.
>
> I use vinyl tubing slipped over the ends of the strips to anchor the corners.
> Releasing
> two corners, I can swing the strips parallel for easy transport if I want to
> take the antenna down.
> So far, although it looks fragile, it has handled 55 mph on country roads,
> and an encounter
> with a tree branch mere slipped off a corner tube, no damage.
>
> Cut to design dimensions, I get nearly flat SWR and wide bandwidth. Haven't
> measured the gain,
> but it seems respectable. While its only 3 elements, its ready to go without
> any set-up.
> For some rovers, it might fit the need.
>
> 73,
>
> David AB2YI
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> VHFcontesting@contesting.com
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>
>
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