Topband: Elevated Radials

[Tom Rauch]

Hi Federeco,

> And next: it seems that the use of this system is not for space problems ,
> but to gain equal currents flowing trough radials and so omni pattern. Can
> somebody explain how this work considering the difference between connect
> 4 quarter wave to coax braid and 4 wave/8 after a coil ??? 

Most people lost sight of the fact this was just an article  that 
assumed equal current in radials somehow cancels the field below 
the radials and reduces losses.

That theory is not good at all, unless the radials are very very high 
above earth. The articles plainly state field strength measurements 
were never made. 

You can carefully balance current in the radials, but it essentially 
does nothing for loss if the radials are close to earth.  
We may not like that, but that is how the real world works.

If I were you, I'd use as many full size radials as I could. The more 
the better. If you only can use few radials, insulate and elevate 
them. But unless your antenna is over salt water you will have loss 
in the earth under the radials unless you use a lot of them.

I'd totally avoid short radials, unless you just have no room. They 
will always be lossier than full size radials.

 
73, Tom W8JI
w8ji@contesting.com


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