[TowerTalk] Another aluminum question

[Alex Malyava]

yeah, you right, it sounds reasonable. I know there are poles made by
SpiderBeamers - 12 and 18 meters long. They are quite expensive, but it is
not big deal...
The other thing worrying me is bandwidth. I think the narrower you go with
wire - the narrower the antenna is.

I will think about it.

2007/12/7, Jim Lux <jimlux at earthlink.net>:
>
>
>
> -----Original Message-----
> >From: Alex Malyava <alex.k2bb at gmail.com>
> >Sent: Dec 7, 2007 2:11 PM
> >To: towertalk at contesting.com
> >Subject: [TowerTalk] Another aluminum question
> >
> >Hi,
> >that's me again with a question very related to the previous one :)
> >
> >I recall a lot of discussions of verticals in this reflector - verticals
> >build out of irrigation pipes or build for permanent installation etc.
> >
> >I want to build a vertical out of aluminum pipes from TexasTowers - the
> only
> >source of telescopic tubing I know about. That vertical suppose to be
> >portable - I have no place for it at home, but would like to take it
> >overseas or at least to Poconos, PA where we rent a house once in a
> while.
>
>
> You might consider a sort of inbetween strategy.  Get one of the very
> lightweight collapsible fiberglass/carbon composite poles  (a 20 footer is a
> couple pounds or so... longer ones are available) and use it to support a
> single wire to a loading network at the base.  (there are portable flag pole
> for banners and such) Very fast to erect, pretty stable, very easy to carry
> around.  Radials can be a bunch of pieces of wire with little shotbags at
> the end (ankle/wrist weights work well) to hold them down.
>
>
> I think if you do some modeling, you'll find that the performance
> difference between something like a AWG 20 wire and a 1" diameter tube isn't
> all that huge.  The losses aren't so much in the radiator itself, as in the
> ground losses, etc.     Might want to carefully check the benefits from
> added height.  The extra efficiency from 3 or 4 more feet might not be worth
> it.
>
> You can build a pretty low loss loading network that would fit in
> something like a plastic tool box.
>
> The reason to go to irrigation pipe, aluminum tubing, etc., is if you need
> it to be sturdy and survive the weather.  In a portable operation, if it
> falls over, you just pick it back up.
> (Of course, if your portable operation is on some gale-blasted rock
> sticking out of the North Sea... maybe the sturdier scheme might be more
> appropriate)
>