[sdiy] when and why use stranded?

[harrybissell]

"J. Larry Hendry" wrote:

>
> Hmmm.  I'd be interested in hearing why you object to that.  I always have
> thought that the skin effect or RF frequencies made stranded a better
> choice.  Of course, a tube is a better choice at some point.

In the case of Litz wire... the skin effect is fully usable, as each wire has an
undisturbed
"skin" (outside of the cross section of each strand).  In a stranded wire, there
are "short
circuit" points all over the place...everywhere one strand touches another.
Will the RF
take the strand, or jump to the next one ? God knows (and you don't).  Flexing
that wire
could change that picture drastically !!!

The other side effect of Litz wire is that the individual inductance of each
strand is in
parallel with all the others, dramatically reducing the total inductance.

And it is a total bitch to strip as well !!!  (each strand must be stripped
separately, usually
with a torch, or solder pot !!!)

Still, stranded wire excells for most of our uses, for other reasons than
impedance

H^) harry