[TowerTalk] Radials, contd.

[Rob Atkinson, K5UJ]

If you were going to try the Y idea, it would be better to flip the Ys so 
you have two radials tapering into one.  Here's why--in the near field, you 
have most of your return current and that is where you want more wire for 
lower resistance and more current return.  Farther out it is not as 
critical.   You could achieve this by putting down 60 1/8 lambda radials and 
ending them with a circle of wire, i.e. all your radials fanning out inside 
a wire circle.  Then, attach 30 1/8 lambda radials to the circle to complete 
the distance, one to every other of the inside 60.

But, isn't this a lot of hassle for a ground system that may use almost as 
much wire and may or may not matter?  Because you seem to be attempting a 
permanent, serious, and long term low band vertical effort with your 90 foot 
insulated tower,  why not do it right all the way?   I would spread the cost 
out by putting down 30 1/4 w/l radials, leaving space on the ring every 
other one, then a few years later when you can afford it, go back and fill 
in the spaces with another 30.

73,

rob / k5uj

By the way, on the subject of radials, I was in Home Depot a couple of days 
ago to see about renting some power tools and I discovered in their rental 
tool department, they had a small gas powered cable laying trencher 
available.   if you do not want to lay your radials on the ground and let 
the grass grow over them, which is what I did, this little trencher might be 
the ticket.  I don't recall what it cost to rent it for a full day--I think 
it was around 20 to 30 dollars.



<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>
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-----
>
>     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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