> Solid is the way to go. As I understand it, stranded wire
can oxidize and therefore lose "contact" or have high
resistance between each strand. Since it's the surface area
of wire that carries the electrons,
The problem is magnetic flux. The closer to the center of
the area carrying current, the more flux surrounding that
area. More flux makes inductance progressively higher in
areas closer to the center of current flow, so current moves
or "pushes" to the outside edge of each stand.
If I put two strands close together and in parallel, HF
current tends to move to the outside edge of each round
conductor away from the other strand!
Contact or not, current moves out to the outer edge of each
outside strand at high frequencies. Smooth round conductors
or smooth solid flashing are more effective in high current
RF conductors than stranded or braided conductors. This is
why flat strip conductors, woven conductors, stranded
conductors, and multi-turn transmitting magnetic loops have
noticeably more conductor loss than similar sized loops made
from a single turn of a smooth round tubing.
I can't think of a reason it wouldn't apply to lightning,
although smooth wide flashing has less inductance than a
narrow round conductor. I would use a wide flashing first,
and then a round conductor (hollow or solid) second. Braided
or finely stranded or woven strands would be way down the
list.
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|