I'm not sure, but can't such designs be modeled in Yagistress,and isn't
there more than one way to skin a cat? This sounds very much like the
Telrex approach - remember those elements with no visible sag? VE1JF
and others can offer practical experience with extreme environments and
a different approach - low wind area and flexibility to match.
73, Pete N4ZR
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On 1/23/2010 3:10 PM, Gene Fuller wrote:
> 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
>>
>>
>> _______________________________________________
>>
>>
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>
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