> -----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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