Why? It's a great discussion (and on topic) and a lot more interesting than
some of the other dribble that's been posted.
Jim N9WW
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Robert
Sent: Sunday, January 24, 2010 5:11 PM
To: Tower and HF antenna construction topics.
Subject: Re: [TowerTalk] lp V stepIR
Can this dialogue be continued elsewhere, like perhaps to a more appropriate
LP reflector?
----- Original Message -----
From: "Gene Smar" <ersmar@verizon.net>
To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Sent: Sunday, January 24, 2010 11:16 AM
Subject: Re: [TowerTalk] lp V stepIR
> Gents:
>
> Fig. 5 in the URL is a good depiction of how only a few of the total
> elements are actually active on any one frequency. If one could run
> similar
> models for increasing frequencies across the design BW of the LP one would
> see the peak current move from the back of the LP (longer elements)
> towards
> the front. It is for this reason that the gain of an LP is considerably
> lower for a given boom length than a similar Yagi - only a few elements
> out
> of the six or eight or ten are active at a time. However, the SWR is
> maintained at a low level throughout the entire BW, the main advantage of
> LPs over Yagis.
>
> 73 de
> Gene Smar AD3F
>
>
> ----- Original Message -----
> From: "jimlux" <jimlux@earthlink.net>
> To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
> Sent: Sunday, January 24, 2010 1:30 PM
> Subject: Re: [TowerTalk] lp V stepIR
>
>
>> Stuart Browne wrote:
>>> Has anyone built an inverted LPDA? Not practical unless you have the
>>> land
>>> and towers to support it but looks cheap to build and rugged. If you had
>>> the
>>> height it looks practical for 7-30 mhz.
>>>
>>>
http://plasma.newcastle.edu.au/plasma/research/tiger/venice/Inv_V_antenna_pa
per.pdf
>>>
>>> Stu,
>>> WH6H
>>>
>>
>> This kind of thing is a mainstay of the commercial HF broadcasting
>> world.. take a look at the TCI website. They even make ones that
>> rotate! (you move the base around)
>>
>> A HF broadcast station near me (KVOH) has something that looks much like
>> this, using two towers.
>> _______________________________________________
>>
>>
>>
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>
> _______________________________________________
>
>
>
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