Topband: 160 metre vertical with 'top loading'

Paul Christensen w9ac at arrl.net
Wed Apr 27 07:16:53 PDT 2011


> A current decrease (meaning less current at one end that at the other)
> is not a loss, and it's far from being unexplained.

A good starting point is here.  Specifically, scroll down to: "Why the Net 
Current is not Constant Through a Loading Coil?"

http://www.w5dxp.com/current.htm

It's easy to fall back only to lumped analysis of Kirchoff's Law and assume 
that current into an inductor must equal the current out of the inductor, 
absent loss.  But I don't believe Kirchoff's Law takes into account standing 
wave current and has resulted in intense debate about RF current 
distribution through loading coils as well as whether or not the 
distribution "replaces" the missing physical part of the vertical radiator.

It comes down to using the right laws for the right application.  The laws 
have their limits based on application.

Paul, W9AC
 



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