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Re: [TowerTalk] Balun Recommendation

Subject: Re: [TowerTalk] Balun Recommendation
From: Jim Brown <>
Date: Mon, 16 Apr 2012 08:55:48 -0700
List-post: <">>
On 4/16/2012 7:30 AM, Jim Lux wrote:
> I think it's in a zone of "cost to build yourself, counting time" and
> "buy retail" where it just doesn't pencil out.

Jim, we're at cross purposes here.

Somehow, you're missing the point that my primary beef with commercial 
products is not their cost, but simply that their designs are so bad 
that they are essentially useless. The technical basis for this 
statement is developed in considerable detail in several pieces that are 
on my website.

With almost no exceptions, there are virtually no technical specs on 
so-called "baluns" beyond power rating -- the only exception I've seen 
is for a few of Array Solutions' chokes, for which impedances at a few 
frequencies are published, but they're strings of beads, they aren't 
very good chokes.  By contrast, the response curves of the W3NQN filters 
ARE published, and anyone who has built high performance filters knows 
that engineering that goes into building them makes them worth the cost.

Except (possibly) for protection from freeze/thaw cyless, there is no 
good reason for a common mode choke consisting of winding multiple turns 
of coax through one or more cores to be in a box at all!  The "labor" 
consists of running the coax through the core(s), and if there are 
multiple cores, lashing them together with ty-wraps. If they're on a 
wire dipole, or on coax coming from a vertical, you're done. If they're 
on a typical beam, the coax at both ends of the choke simply must be 
mechanically secured to the boom.  The only reason for putting this kind 
of choke in a box is so that you can sell it to someone!

The lower cost  bifilar-wound chokes I've designed that DO require some 
sort of packaging, but I'm not at all convinced that they needs to be in 
a BOX.  What IS needed is a means of adding SO239 connectors and strain 
relief so that they can be patched into an existing transmission line.  
My neighbor, W6GJB, who is much better with mechanical design than I am, 
worked up a nice method that uses PVC plumbing parts to hold the 

I'm quite willing to pay good money for good products -- there are two 
K3s and two Ten Tec Titan amps on my operating desk in an SO2R setup, 
and both have W3NQN filters between K3 and power amp that were purchased 
from Array Solutions.  Thanks to 40+ years employment in engineering, 
technical sales, and consulting, I have a pretty good grasp on the cost 
issues you've outlined, and I have no quarrel with them.

73, Jim Brown K9YC

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