The general behavior for bent antennas less than a halfwave is that
there is a *mild* advantage in the direction opposite the bend versus
the direction with the bend, e.g, if the wire goes up and bends west,
the hemisphere of advantage is centered on east. As the horizontal
section becomes shorter, the mild morphs toward undetectable.
73, Guy.
On Wed, Dec 9, 2009 at 12:22 PM, alan eshleman <oakame@yahoo.com> wrote:
> ...and another question: I have an Inv L (appx 80 vertical and 50 feet
> downsloping "horizontal") with ground radials (#16) and am wondering how much
> directionality the horizontal wire gives. The horizontal wire here runs
> roughly east-west. It's a reasonable DX antenna--I can work EU from the West
> Coast, which isn't always easy. For domestic contests such as the ARRL 160 M
> contest (it's a domestic contest from the West Coast and a different contest
> from the East Coast, but let's not get into how unfair that is) I wonder how
> much improvement I'd get if the horizontal wire were broadside to the East.
>
> All feedback welcome.
>
> 73,
>
> Alan/K6SRZ
>
> --- On Tue, 12/8/09, DAVID CUTHBERT <telegrapher9@gmail.com> wrote:
>
>> From: DAVID CUTHBERT <telegrapher9@gmail.com>
>> Subject: Re: Topband: inverted L pointers please
>> To: jwatrous@sonic.net
>> Cc: topband@contesting.com
>> Date: Tuesday, December 8, 2009, 6:45 PM
>> John,
>>
>> the goal is to make an inverted-L that works as well as a
>> quarter wavelength
>> vertical. Given a very good ground system a rather
>> vertically short
>> inverted-L is nearly as efficient as the vertical. Given a
>> poor ground
>> system a taller inverted-L will give better performance.
>> Inverted-L
>> radiation resistance:
>>
>> 40' vertical and 95' horizontal, 12 ohms
>> 50' vertical and 85' horizontal, 22 ohms
>> 60' vertical and 75' horizontal, 29 ohms
>> 70' vertical and 65' horizontal, 43 ohms
>>
>> Dave WX7G
>>
>> On Tue, Dec 8, 2009 at 5:45 PM, <jwatrous@sonic.net>
>> wrote:
>>
>> > I'm about to build an inverted L for 160 after 50
>> years of ham radio.
>> > I have looked at many webpages, but is there one you
>> experts can recommend?
>> >
>> > Thanks in advance,
>> >
>> > John
>> >
>> >
>> > John Watrous, K6PZB
>> >
>> > 707 360 5496 cel
>> >
>> > john@jwatrous.org
>> >
>> > _______________________________________________
>> > 160 meters is a serious band, it should be treated
>> with respect. - TF4M
>> >
>> _______________________________________________
>> 160 meters is a serious band, it should be treated with
>> respect. - TF4M
>>
>
>
>
> _______________________________________________
> 160 meters is a serious band, it should be treated with respect. - TF4M
>
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M
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