[TowerTalk] Feedlines: inside or out on tower?

[Jim Brown]

On 8/19/2012 10:08 AM, K7LXC at aol.com wrote:
> I'll second that. Cables run inside a tower get  some sort of Farraday
> cage effect. Is it real and effective? I don't know.

Skin effect causes RF current to flow on the outer surface of a 
conductor, so cables run inside a tower will carry less RF current than 
cables run outside the tower.  That said, there can be some inductive 
coupling between a tower leg carrying current and cable taped to it.

> It is  a real pain. I much prefer cables outside the leg - easy to install and easy to  replace (well, relatively easy anyway).

My neighbor, K6XX, who does a fair amount of tower work and does all of 
mine, thinks otherwise.  The initial install of my tower was LDF4-50, 
taped to the inside of one leg, and it went up quite easily.   I've 
recently acquired some 7/8-in hard line, and plan to install it the next 
free weekend.  He says it's easy to do.

73, Jim K9YC