My experience using a 3x3 foot grid as a ground screen
is somewhat analogous to your "Y radial" idea.
You often read that the ends of the radials must be spaced
less than so many wavelengths. At 3 ft, my grid easily
meets this criterion. However, I found that for proper
operation, I still needed 60 radials originating at the
vertical. Thus the Y radials are unlikely to work as you
hoped.
Rick N6RK
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com]On Behalf Of James Bloomfield
> Sent: Thursday, August 02, 2007 5:26 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Radials contd.
>
>
>
>
> Good Morning
>
>
>
> I need an education, edification, and elucidation.
>
>
>
> In Brief the project is a 90 ft. Rohn, insulated from ground, fed
> with an ?L
> ? C? network for 160 and 80. This tower is described in the ON4UN Book on
> Lowband DXing.
>
>
>
> >From reading Tower Talk I have decided to purchase commercially available
> tower leg insulators. Something about falling off a 90 foot
> tower that does
> not appeal to me.
>
>
>
> Now comes to the radials. I need to save money and I have
> thought of a way
> to use less wire, perhaps.
>
>
>
> Definition:
>
> Type One Radial. A radial wire that originates at the base of
> the tower and
> goes in a more or less straight line away from the base.
>
>
>
> Type Two radial. A radial wire that is ?Y? shaped. The stem of the ?Y?
> originates at the base of the tower and goes one half the distance of the
> radial, at this point it is joined by two wires that continue out to the
> perimeter.
>
>
>
> Using both types of radials the end points are the same space at the
> perimeter of the radials circle.
>
>
>
> My questions are:
>
>
>
> Can someone with the skills to use antenna modeling software compare:
>
> 120 ¼ wave Type One radials with 60 Type Two radials.
>
>
>
> 60 Type One radials with 30 Type Two radials.
>
>
>
> In reading it seems to me that after 60 ¼ wave you get to diminishing
> returns. The time and money involved in going from 60 to 120
> does not give
> a doubling of signal ? or even a 50% increase in the signal.
>
>
>
> So I guess the bottom line is, if I install 30 Type Two radials
> will I have
> the same signal as 60 Type One radials and if I add to the 30 Type Two is
> there a cost/signal benefit.
>
>
>
> Removing Raccoons with a S&W 357 Magnum is very effective however the down
> side is if I do that two often I?ll have to learn to cook, get a job to
> support myself, and move to a doublewide in the woods.
>
>
>
> Thanks
>
> KV4FE
>
> Jim
>
>
>
> On the Suwannee River
>
>
>
>
>
>
>
> _______________________________________________
>
>
>
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>
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