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While waiting for my Force-12 Falcon to arrive, I decided to slap together a linear loaded rotatable dipole for 20M that would also work well on 17M (and other bands as a bonus).

I had some aluminum odds and ends and came up with 2 elements that are 10' 6" long on each side of the center fiberglass insulator and then added 2 lengths of 450 ohm ladder line that were just under 4' long. My coax connects to a 1:1 Cal - AV current choke and then to the center bottom side of the ladder line. The ladder line is taped to the 10' 6" dipole elements - shorted together at the far (outside) ends, and the "top" ends of the ladder line connect to the aluminum elements. The ladder line is taped right to the aluminum dipole elements, and is very "stealthy" indeed. I only run 200W, but my guess is that this would handle quite a bit more.

The antenna is resonant on the CW portion of 20M, and tunes up 1.5:1 or less with my rigs internal ATU on 17M, 12M and 10M. It needs a little help from my Ten Tec 238B on 15M, but it works very well on all of these bands. It works well up into the phone bands, and is quieter than I had expected (but we aren't getting the nasty flares that we did last year).

I got the idea from thinking about how Force-12 uses linear loading and sleeve coupling to their advantage, but also from this excellent article:

http://www.arrl.org/tis/info/pdf/0207040.pdf

And just applied the same thinking to a shortened 20M antenna. Of course, now I am wondering what the spacing would be to turn this into a 2 element 20M monoband yagi. I have a nice piece of aluminum tubing that I could use as a boom!