[TowerTalk] SECOND FLOOR SHACK

[Jim Brown]

On Wed, 12 Jul 2006 16:56:31 -0700, JC Smith wrote:

>Sorry, guys, but I must disagree.  While a shack ground is NOT a sink for
>noise, it IS far more than lightning protection.  It is supposed to provide
>a low-impedance path for stray RF that inadvertently runs around in the
>shack. 

"Supposed" is exactly that -- only in your imagination. There is NOTHING 
magical about the earth that causes a connection to it to reduce "stray RF" 
in your shack. You can disagree, but the stuff you are quoting is essentially 
an old wives tale. 

Compute (or measure, if you can) the complex impedance of that "ground" wire 
from one end to the other at the frequency you are transmitting. If you 
didn't blow the math, you will find that it is NOT a low impedance path to 
earth. And if it does carry RF, it will radiate that RF (and receive whatever 
RF is around it). 

Jim Brown K9YC