BOOTY MONSTER,
I think if you sort of read between the lines, you sort of get the idea that ol'Sean had a general idea of what he was after, but no specific solutions to any one particular part of his antenna. I'm willing to bet that 'coil' thingy was a lot of 'try it and see', rather than an exact dimensions thingy. And after seeing some of the things he did try, and his reasons for not doing it that way (in his particular case!), tends to prove that out. His "what ever you happen to have" philosophy is absolutely normal for any antenna experimenting. If it works, it works. Worry about making it 'better'/prettier/easier later.
I've found that 'ring' method is just exactly what he said it was, 'touchy'. Even if it's commercially made, it's 'touchy' to tune, doesn't take much movement of that shorting-bar to make a big change, once you get to the 'ball park' stage of adjustment. (I like that 'bar-stock' idea. No idea where to find it, but it sounds reasonable.)
One characteristic about using a coil, or taped coil, for matching is that it can be made less subject to variations because of weather by putting it inside something. The bigger that enclosure, the further it is away from the coil, the less interaction there will be. If it intrudes into the 'field' around that coil, it will change it's characteristics. After some undetermined point, that size of enclosure can get really ridiculous, so some reason is required there.
What to use for the antenna elements/conductors? Well, it has to be 'stiff', able to support it's own weight without bending, OR, enclosed/attached to something that will do that for it. What? Beats me. What'cha got that will do that, or what can your imagination supply that will do that? Got a tree with a limb overhanging a fence 30 - 50 feet above ground? Hang a wire from it and use that fence as the 'radial's. It works. Maybe not the 'best' in the world, but if it works, who cares?
There's another option to that 'ring' or coil. All that's needed is something that will supply the required impedance match, right? Once upon a time, ya-da ya-da ya-da, I saw such a thingy made from two pieces of coax. One sort of long from the base of the vertical element, and a shorter shorted 'stub' at the other end of the longer piece where it ended in an SO-239 connector for the feed line. (Wish I could find those dimensions again, but can't...Rats! And am too lazy to find them by experimenting.) The whole thing was suspended from a tree limb over a chain-link fence. It worked just fine. (This was at work. Had so much 'stuff' hung/hanging from that tree that I eventually caught @#$$ over it an had to remove it all. Mostly, sort of. Used so many wrenches, rocks, whatever for 'chunkers' that got tangled/hung-up, I ran out of tools. An old sock filled with sand works great!)
All kinds of things you can try, just takes a little imagination...
- 'Doc
It ain't easy being this cheap.
