Towertalk
[Top] [All Lists]

Re: [TowerTalk] 4 square for 80

To: towertalk@contesting.com
Subject: Re: [TowerTalk] 4 square for 80
From: Steve London <n2icarrl@gmail.com>
Reply-to: n2ic@arrl.net
Date: Sat, 24 Sep 2016 08:15:49 -0600
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
K9YC writes:

I disagree with this advice, Tim. Such a choke is strongly inductive below about 30 MHz, 
so > its common mode Z will be cancelled, at least in part, by the capacitance of a 
feedline > shorter than a quarter wave. A multiturn choke wound on one or more #31 
cores is > predominantly resistive, so performance is far less affected by the 
impedance of the common mode circuit.

Most of the comments on 4 squares have been qualitative, such as "my 4-square works fine with 1 twisted, semi-elevated, half-radial". However, in K3LR's case, he has actual measurements of the performance of his 4-squares, including F/B and F/S measurements. If there was a problem with the W0IYH-style chokes, wouldn't it show up in his measurements ? How much better would the performance be with a multiturn choke ? Over real ground, in the presence of real, possibly interacting structures within N wavelengths, isn't there a finite limit to the performance, regardless of your choice of "excellent" vs. "superb" common-mode chokes ?

73,
Steve, N2IC
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

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