Topband
[Top] [All Lists]

Re: Topband: Air wound coil

To: <topband@contesting.com>
Subject: Re: Topband: Air wound coil
From: "Paul Christensen" <w9ac@arrl.net>
Date: Mon, 3 Sep 2018 07:20:56 -0400
List-post: <mailto:topband@contesting.com>
I ran the same model in 4Nec2 as below but changed the hat from the traditional 
two wires to four, spaced 90 degs.  Complex base Z is near 16+j0.  Even though 
two symmetrical top-hat wires produce little radiation, four wires result in 
wires that are only 24 ft long to achieve resonance -- versus 41 ft with only 
two wires.  Getting to six would result in a smaller top hat but may not be 
worth the mechanical hassle.    

>"4Nec2 shows that with a 68 ft. thin radiator, resonance can be achieved with 
>wires roughly 41 ft. per side.  With a ground field of 60 radials, 90 ft long 
>on sandy ground, 4Nec2 reports a base impedance of 15.4+j2.5."  

Paul, W9AC

_________________
Topband Reflector Archives - http://www.contesting.com/_topband

<Prev in Thread] Current Thread [Next in Thread>