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Topband: 160 metre vertical with 'top loading'

To: "160 reflector" <topband@contesting.com>
Subject: Topband: 160 metre vertical with 'top loading'
From: "Tom Boucher" <tom@telemetry.demon.co.uk>
Reply-to: Tom Boucher <tom@telemetry.demon.co.uk>
Date: Sun, 24 Apr 2011 20:01:59 +0100
List-post: <topband@contesting.com">mailto:topband@contesting.com>
On the eternally recurring argument about current into and out of a loading 
coil, here is the way my simple mind has always understood it:

W8JI is correct in that the current into a perfect inductor must equal the 
current out of it. It's a piece of coiled wire so where else can the current 
go? Tom's assumption here is a 'perfect' inductor with no distributed 
capacitance.

K3BU is also correct because he is assuming a practical inductor, with a finite 
length and distributed capacitance to ground. That's where the missing current 
is going, through the distributed capacitance to ground and hence lower output 
current from the top of the inductor into the antenna.

Both right, so why the disagreement?

73
Tom G3OLB
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