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[TowerTalk] Antenna positioning in the wind

To: <towertalk@contesting.com>
Subject: [TowerTalk] Antenna positioning in the wind
From: w8ik@ibm.net (Joe Subich, W8IK)
Date: Mon, 7 Dec 1998 23:20:34 -0500


> -----Original Message-----
> From: owner-towertalk@contesting.com
> [mailto:owner-towertalk@contesting.com]On Behalf Of N0OEL@aol.com
> Sent: Monday, December 07, 1998 10:54 PM
> To: PAUL924@aol.com; Towertalk@contesting.com
> Subject: Re: [TowerTalk] Antenna positioning in the wind
> 
> 
> 
> Paul, your question has be argued for years!    But consider the 
> following:
> 
> If you put the tips into the wind you are easier on the beam as 
> the boom has the most strength.   But the windload on the thicker 
> boom has, in most cases, more windload therefore more windload 
> on the tower.

Based on information that Roger Cox of HyGain has previously posted 
to the Towertalk group, putting the boom broadside to the wind is 
best of HF antennas.  I'll attach the information below ... but 
at HF there is far more wind load in the elements than the boom 
by two, three or more to one.  Of course, the boom is significantly 
stronger than the thinner elements. 

>> 
>> Antenna          Projected Area* in sq. ft.
>> Model              (elements)  (boom)
>> 
>> TH11DX              18.0        4.1
>> LP-1009AA           17.1        4.5
>> TH7DX               11.5        4.1
>> TH5MK2              10.1        3.2
>> DB1217              10.0        2.4
>> Explorer-14          9.8        2.4
>> TH3Mk4               6.9        2.4
>> TH3jr                4.7        1.3
>> TH2Mk3               4.7        1.0
>> 
>> 205CA               11.5        5.8
>> 204BA                9.3        4.3
>> 203BA                7.3        2.7
>> 155CA                6.2        4.3
>> 153BA                3.8        2.1
>> 105CA                4.1        4.1
>> 103BA                2.6        0.8
>>  66DX                2.1        4.1

Note that ONLY the 6 meter antenna has more wind load in the 
boom than in the elements. 

73,
   ... Joe Subich, W8IK/4  ex-AD8I
       <W8IK@IBM.NET>
 

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