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


Ever seen the coax used on TV transmission lines? In rough numbers is is
a pipe about 6" in diameter with another pipe about 1" in diameter held
centered inside the larger one by spacers.