Two factors. One is surface roughness. The other is caused by the
current having to continually move from one group of wires to another as
it travels.

Interesting, but how do you know the current is moving as you say?

I'm just now doing some research on how significant these
effects are, but so far I've found out they're very noticeable.

Ok. I'm curious: What equipment are you using for the research?


But hey, you don't have to believe me. Make up some coils and measure
their Q -- it's not hard at all. Then stick them outside for a while and
measure them again.

What would be a good way to measure Q?

Or do like most amateurs do -- make the coils,
discover that you can talk to far away places "barefoot", and declare
that they "work".


Uugghh, don't I know.