Hi Joe -
Mostly valid points. However, smaller diameter elements can be strong. The
45 foot linear loaded elements in my design are only 1 5/8 " O.D. . They are
"plytubular" design with up to four internal layers of tubing. 45 feet long,
opened 10 feet out with 1" O.D. extren rod to allow for the linear loading.
Design is good for 100 mph with 1/4" of ice. So far, after about ten years,
it has had up to 85 MPH gusty wind with no ice, and no failures.
Regardless of the antenns model considered, anyone's element design would
have to have sufficient bending moment resistance and therefore cost and
weight, plytubular design allows smaller O.D. and therefore smaller
projected wind surface area.
Gene / W2LU
----- Original Message -----
From: "Joe Subich, W4TV" <lists@subich.com>
To: "'Tower and HF antenna construction topics.'"
<towertalk@contesting.com>; <brahmangou@aol.com>
Sent: Saturday, January 23, 2010 2:12 PM
Subject: Re: [TowerTalk] LP v SteppIR
>
>
>> All things considered from my perspective, The Log is cheap,
>> light , easy, broadbanded, sufficient gain, automatic band
>> switching, unlimited power and duty rating, light wind
>> loading, and directly fed without matching devices or a
>> balun.
>
> Unfortunately, if one wants a log that will hold up to any
> kind of wind for more than a couple years, it is not going
> to be cheap or light. The logs with light weight (small
> diameter) elements are not going to handle either ice or
> the constant vibration of wind. By the time one builds
> enough strength into them, they become heavy and expensive
> like the old Hy-Gain, and Collins designs for the Department
> of State and/or Department of Defense.
>
> By the way, the better performing LP designs are 200 Ohm
> feed systems and require a 4:1 balun or other matching
> system.
>
> 73,
>
> ... Joe, W4TV
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|