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Re: [TowerTalk] 43ft Vertical Feeding Question and Balun type

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Subject: Re: [TowerTalk] 43ft Vertical Feeding Question and Balun type
From: "James Chaggaris" <>
Date: Thu, 20 Nov 2008 10:33:57 -0600
List-post: <">>
A great discussion has been taking place on eham regarding 43' verticals.


Jim N9WW

James E. Chaggaris
PowerOne Corp.
1020 Cedar Ave.
Suite 203
St. Charles, IL 60174
Phn:(630) 443-6500
Fax:(630) 443-6505
Cell:(630) 669-2241

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-----Original Message-----
[] On Behalf Of Pete Smith
Sent: Thursday, November 20, 2008 10:21 AM
Subject: Re: [TowerTalk] 43ft Vertical Feeding Question and Balun type

You clearly need a tuner at the base of such an antenna, rather than in the
shack, but there are a number of possible choices for that service now.  A
more interesting question is what the radiation pattern will look like on
the various bands.  I ran a quick-and-dirty, and it appears that the optimum
(highest-gain)  takeoff angle varies from 26 to 16 degrees on 80-20, then 37
and 57 on 15 and 10.  That obviously makes a big difference in the
subjective reports on the various bands, depending on the distance.

There was a series of articles in National Contest Journal a few years ago,
using NEC-4 to evaluate on-the-ground/buried radials.  The message I took
away from that series was "Them as has, gets."  That is, at a QTH with very
good ground conductivity, the improvement afforded by many radials is
relatively small.  At a QTH with poor ground conductivity, even a full-up AM
broadcast radial field will only get you somewhere close to the station with
very good ground and a few radials.

My 2 cents.

73, Pete N4ZR

At 10:55 AM 11/20/2008, Rick Stealey wrote:

>It would sure seem to me that a 43 ft vertical is essentially a random 
>length antenna.
>I saw the web site too where they offer a balun to go with it.  "It 
>tunes all bands"
>they say, WITH YOUR TUNER in the shack, or at the base of the antenna !!!
>I did a quick and dirty check with 4NEC and got 122-j466 at the base on 
>20 meters, an swr of 38:1 !  A sweep shows an SWR of >9:1 from 7 to 15 
>On 40 m you get 150+j210, an swr of 9:1 On 80 you get 17-j257, an swr 
>of 79:1 !!
>So it would seem to me you have a lot of work to do to match this thing 
>at the base.
>It would not be a good idea to run coax straight into the house with a
>79:1 SWR
>and hope a tuner will fix things.
>I know there is a guy in Chicago on 20 meters running one of them with 
>no radials who comes into NJ 20 over 9 at times and claims no knowledge 
>as to how he does it.
>Guys he talks to rave about his rock crushing signal.  Wouldn't it be 
>interesting to compare his signal in real time with his neighbor 
>running a beam, or a quarter wave vertical.  I mean.... the laws of 
>physics haven't been rewritten lately have they, and I missed out on 
>Rick  K2XT
>Proud to be a PC? Show the world. Download the "I'm a PC" Messenger 
>themepack now.
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