The kite project I hinted at, that may or may not be adaptable for a balloon
did indeed use 450 ohm ladder line. The article is in QST, April 2000 called
'NE2Q's Antenna Fell From the Sky' for those wishing to dig into this.
Basically the dipole dropped straight down from the kite line a couple of
hundred feet below the kite, the ladder line was fed at 90 degrees to the
dipole and was also supported by the kite line, and continued down to the
radio shack.
If the balloon could be used to support a dipole, why not configure like an
upside-down 'Y'- The top leg is then 1/2 the dipole, one arm the other half
and the second arm is the feed line.
As far as lifting power of a balloon goes, consider the fellows that fly the
skies in Lawn chairs, with only party balloons. Also, there is no reason to
use heavier copper wire for a temporary antenna when you can buy aluminum
magnetic wire used for motor windings. Somewhere around here I have a roll
of it I 'got' from Emerson motor when they had a plant here in town. I would
suggest a tag/safety line for any wire in case of wire breakage.
The radials I first mentioned would have to be used on a 1/4 wave vertical,
yes I do know you don't need radials for a dipole. I just don't know how
effective a few radials would be at ground level for a 1/4 wave vertical and
I don't want to open that can of worms again on ground losses.
73 Eric.
> -----Original Message-----
> From: Dave AA6YQ
> Subject: Re: [TowerTalk] balloon supported antenna
>
> 1 foot of 450 ohm ladder line weighs .4 oz, so 500 feet would be ~12.5
> lbs,
> which seems feasible.
>
> 73,
>
> Dave, AA6YQ
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com]On Behalf Of Dave Tipton
> Sent: Tuesday, December 16, 2008 5:30 PM
> To: 'Larry Banks'; TowerTalk@contesting.com
> Subject: Re: [TowerTalk] balloon supported antenna
>
>
> I don't think there is a balloon out there that will hold up 460 feet
> of
> RG213...
>
>
> Even multiple balloons would have a tough time of that.
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Larry Banks
> Sent: Tuesday, December 16, 2008 4:25 PM
> To: TowerTalk@contesting.com
> Subject: Re: [TowerTalk] balloon supported antenna
>
> And the coax should come away from the feed point at 90 degrees for
> ~1/4
> wave...
>
> 73'
> Larry
> W1DYJ
>
>
> ----- Original Message -----
> From: "Alex Malyava" <alex.k2bb@gmail.com>
> To: "Bob Maser" <bmaser@tampabay.rr.com>
> Cc: <TowerTalk@contesting.com>; <ve3gsi@canada.com>
> Sent: Tuesday, December 16, 2008 5:17 PM
> Subject: Re: [TowerTalk] balloon supported antenna
>
>
> > He will need to use BIG baloon then...
> > In case of vertical the workload is the radiator wire only, when
> > dipole needs to lift good length of coax as well.
> >
> > On Tue, Dec 16, 2008 at 5:04 PM, Bob Maser <bmaser@tampabay.rr.com>
> wrote:
> >> A vertical dipole require no radials as it is center fed.
> >>
> >> Bob W6TR
> >> ----- Original Message -----
> >> From: "Eric - VE3GSI" <ve3gsi@sympatico.ca>
> >> To: <TowerTalk@contesting.com>
> >> Sent: Tuesday, December 16, 2008 10:00 PM
> >> Subject: Re: [TowerTalk] balloon supported antenna
> >>
> >>
> >>> Gregg,
> >>> There is a article in this January QST using a balloon loop
> antenna, I
> >>> see
> >>> no reason it can't be resized and used on 160 meters. It might be
> worth
> >>> a
> >>> look at for your project. Also, a few years back in QST there was
> an
> >>> interesting article on using a kite for a 160 meters with 1/2
> vertical
> >>> dipole antenna.
> >>>
> >>> I suspect you would need a pile of ground radial to be effective
> with a
> >>> 1/4
> >>> vertical, while the loop might be a more wire friendly way to go
> and
> >>> possibly safer. Not being a 160 meter kind of guy, I suspect others
> will
> >>> verify the number of radials required for balloon vertical antenna.
> >>> 73 Eric - Ve3gsi.
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Gregg Seidl
> >>>> Subject: [TowerTalk] ballon supported antenna
> >>>>
> >>>> Has anyone ever done this? I want to use a weather ballon to
> support a
> >>>> vertical dipole for 160 during the upcoming contest. I have plenty
> of
> >>>> room
> >>>> with no chance of the antenna hitting or coming in contact with HV
> >>>> power
> >>>> lines. What size ballon,where did you get it from.......??I'd only
> have
> >>>> it
> >>>> up during the contest. Gregg K9KL
> >>>
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