I spoke to one manufacturer of these and they are working on a version
with 3 or 4 top guys that are a combination of wire and "rope" to
effectively create top loading. They are not sure just how much of an
effect it would have and are going to field model it. This is an
interesting concept. DXE has some top hats but they are for the heavy
duty verticals which are not very travel friendly.
On 3/28/2011 1:25 PM, Grant Saviers wrote:
> Top loading the 43' will increase its radiation resistance and thereby
> the efficiency. DX Eng has some top hats in their catalog. Some of the
> Antenna Compendiums have articles. It's an interesting question to
> model this for 160 - 40m. Perhaps there is a "magic" guy number and
> length that preserves some sort of 40m match.
>
> My 40' vertical for 80m had 8 x 6' 0.375" Al horizontal tubes as a
> capacity hat to resonate in the center of the 80m band.
>
> Grant KZ1W
>
>
> On 3/25/2011 7:45 PM, Jim W7RY wrote:
>> Great article! thanks for sharing.
>>
>> 73
>> Jim W7RY
>>
>>
>>
>> --------------------------------------------------
>> From: "Al Kozakiewicz"<akozak@hourglass.com>
>> Sent: Thursday, March 24, 2011 10:12 AM
>> To: "Mike Fatchett W0MU"<w0mu@w0mu.com>;<towertalk@contesting.com>
>> Subject: Re: [TowerTalk] 43 Ft Vertical on 80/160 DX-Pedition
>>
>>> Have you read Phil Salas' article on base loading for this antenna on his
>>> website? http://www.ad5x.com/images/Articles/Match160.pdf
>>>
>>> Al
>>> AB2ZY
>>> ________________________________________
>>> From: towertalk-bounces@contesting.com [towertalk-bounces@contesting.com]
>>> On Behalf Of Mike Fatchett W0MU [w0mu@w0mu.com]
>>> Sent: Thursday, March 24, 2011 1:04 PM
>>> To: towertalk@contesting.com
>>> Subject: [TowerTalk] 43 Ft Vertical on 80/160 DX-Pedition
>>>
>>> I am aware of the issues with this antenna on 80/160. I was curious if
>>> adding a wire T to the top would improve the performance on these two
>>> bands. I am unclear what the length of the T would be or what effect
>>> the T would have on the 30/40. I am not concerned so much with 10m-20m
>>> as we will have other antennas for those bands.
>>>
>>> W0MU
>>> _______________________________________________
>>>
>>>
>>>
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>>>
>>>
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>>>
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>> _______________________________________________
>>
>>
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> _______________________________________________
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