On Sun, 16 Nov 2008 21:44:07 +0000, Dave wrote:

Richard Harrison wrote:
Dave wrote:
"High power coaxial transmission lines have hollow center conductors."

Yes, and the metal which could have filled the hollow space would add no
conductivity at HF.

Best regards, Richard Harrison, KB5WZI


Power handling and efficiency increase as the frequency decreases; a
solid center conductor doesn't help at LF either.

http://www.myat.com/index.html


As a matter of fact skin depth tends to keep power conductors (50/60
Hz) below 1 inch (25 mm) diameter. It becomes easier and cheaper to
"quad them up" (four conductors a couple of hand spans apart).