[TowerTalk] Fw: Vertical Dipoles

[Gene Fuller]

----- Original Message ----- 
From: "Gene Fuller" <w2lu at rochester.rr.com>
To: "Jim Brown" <jim at audiosystemsgroup.com>
Sent: Wednesday, November 18, 2009 4:12 PM
Subject: Re: [TowerTalk] Vertical Dipoles


> If I had a 100 foot tower, which I do, I would, and did do, for 160 - 
> quarterwave slopers, for 80 - bent vertical dipoles. For 10-40 I built an 
> LP, but a combination of 40 meter inverrted V or horizontal dipole and 
> tribander or yagis - all will work great just because of the height.
> Gene / W2LU
>
> ----- Original Message ----- 
> From: "Jim Brown" <jim at audiosystemsgroup.com>
> To: "Tower Talk List" <towertalk at contesting.com>
> Sent: Wednesday, November 18, 2009 11:55 AM
> Subject: Re: [TowerTalk] Vertical Dipoles
>
>
>> On Wed, 18 Nov 2009 10:14:41 -0600, Rob Atkinson wrote:
>>
>>>I don't think there is any relevance in comparing an inverted V to a
>>>vertical dipole.
>>
>> The relevance is a practical one. Let's say I have a rope in a pulley
>> at 100 ft (or a tower that I can climb) and I want to support an
>> antenna, and I have no other supports (or at least nothing high). What
>> antenna should I try to support from that single point -- a vertical
>> dipole or an inverted Vee?  The Inverted Vee is clearly superior, as
>> shown by modeling in NEC, and by the analysis in the paper Rob has
>> cited.
>>
>> Rudy's design, and the ones that David and Ian are describing, are
>> quite ingenious, and interact differently with the earth by virtue of
>> their design (and height). They are also CONSTRUCTED very differently.
>> They are the answer to a different real estate problem -- I can erect
>> a tower of modest neight and I want to work 160M (or 80M). :)
>>
>> BTW -- the interaction with the earth is strongly dependent on HEIGHT
>> of the antenna. When I modeled my vertical dipole, I tried it at
>> several heights, and found that while "higher is better," it isn't
>> enough better to make it a good antenna. :)
>>
>> 73,
>>
>> Jim K9YC
>>
>>
>>
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>