"JN" wrote in message
...
I am planning a two band antenna for 30 and 80m using linear traps.
The idea is to build the antenna of zip-cord type line 140ohm vf 0.73.
Trap is made using 1/4 wave shorted stub, decoupling occurs at the open
end.

Thanks to everybody for valuable comments.
Special thanks to Jim K7JEB, who made the simulation and verified that the
antenna
works as expected.

After much confusion with the text graphics, I learned the lesson to never
use them again

So here is how the antenna works
http://farm4.static.flickr.com/3078/...7c03acc4_o.jpg

I am going to use this kind of material, which is very commonly used by
telephone companies here.
http://www.saunalahti.fi/hohtola/ham/killu/killu.html

And here is how it will be made:

http://farm3.static.flickr.com/2072/...5653e9b9_o.jpg

Why not normal traps? Easier to build
Why not parallell dipoles? Much shorter
You get three bands if needed very easily

73 Jouko OH5RM