Quite literally, almost anything that conducts electricity can be used as an antenna. That doesn't say how well it will work, only that it will 'work' to some extent. That opens up a huge range of possibilities which then get narrowed down by the practical aspects of what you have available for use (space to put the thing in, wire/tubing/feed line/etc.), and what frequencies you want to use it on.
How well an antenna 'works' is relative. If it's multi-band then you can't expect 'perfection' unless a lot of work/effort/complexity is put into it. It's difficult to combine the characteristics of several antennas into one 'simple' "works anywhere" type antenna. Don't expect 'miracles'.
Now that that's out of the way, bigger, higher and simpler is nice! The use of a tuner is also nice, they make some really 'odd' antennas usable. Probably the simplest antenna to put together is a doublet fed with parallel feed line through a tuner. It's not always easy, but it's certainly 'do-able' for -some- people, not so 'do-able' for others.
Why parallel feed line instead of coax? It's able to withstand more 'abuse' from voltage/current, can handle a higher SWR than coax before you damage it. It certainly isn't as 'easy' to use as coax, but it isn't all that difficult either.
So what space do you have available to put an antenna into, and then, what do you have available to make that antenna out of?
- 'Doc
