[TowerTalk] Trees and Verticals

[David Gilbert]

That would be an interesting configuration to model in the manner that 
Jim Lux suggested (using a set of resistive wires to simulate the tree), 
but I'm pretty sure that the losses would be significant if the tree 
itself was indeed lossy.  Normally the fields inside a closed structure 
are minimal, but that's because (unless I am mistaken ... which is 
entirely possible) the E-fields generated by current through the various 
wires/surfaces repel each other.  If you put a lossy medium in the 
middle they get absorbed before they repel each other.

I'm guessing that would be the second worst way to use a tree as far as 
efficiency is concerned.  The worst would probably be to bore a long 
hole down the center of the trunk and run the wire through it.  
Stealthy, yes ... efficient, no.

73,
Dave   AB7E



On 12/28/2011 1:41 PM, Dan Schaaf wrote:
> What happens if you make the vertical as a cage of vertical wires around the tree ? Joined at the top and joined and fed at the bottom. The tree is in the center of the cage.
>
> Cage wire antennas seem to have a broad bandwidth. But what happens to the tree losses when the tree is caged ?
>
>
> Best Regards
> Dan Schaaf
> K3ZXL www.k3zxl.com