[Elecraft] Very short 80m antenna

Vic Rosenthal 4X6GP k2vco.vic at gmail.com
Sun Jan 22 07:34:54 EST 2017


Today I am limited to the bands from 7 MHz and up and I want to get on 
80m. My space is very limited, and in particular (due to the need to 
rotate my existing dipole), there is no way to put up a vertical more 
than about 3m high, and no room for radials longer than a few meters.

But the location is 35m above the ground and it is possible to add 
another rotatable horizontal dipole to my mast.

So I am thinking about a 6m long dipole made of aluminum tubing. I have 
some that is about 20mm in diameter. I will make capacity hats for each 
side to add some end loading.

Yes, I know the bandwidth would be very narrow. But I could live with a 
3:1 SWR bandwidth of 30 kHz.


I'm thinking about two possible configurations for loading coils: one 
coil in the middle, or two coils, each about halfway down each side of 
the dipole.

I know that two coils would produce a more efficient antenna. But the 
one coil in the middle has two big advantages: it would allow me to feed 
the antenna via an isolated link, which would solve the common-mode 
problem without requiring a balun, and it would allow for easy tuning 
and matching.

So what do you antenna experts think? One or two coils? Or is it just 
crazy to expect anything from such a short antenna?
-- 
73,
Vic, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/


More information about the Elecraft mailing list