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Re: Topband: Inverted L improvements - Part 3 (now with data)

To: Todd Goins <tgoins@gmail.com>
Subject: Re: Topband: Inverted L improvements - Part 3 (now with data)
From: Mike Waters <mikewate@gmail.com>
Date: Mon, 21 Jan 2019 21:56:01 -0600
List-post: <mailto:topband@contesting.com>
Man, that seems awfully broad! Somewhere, you have losses, my friend.

You ARE measuring directly at the feedpoint, aren't you? And with the
antenna analyzer FLOATING (not touching you, the earth, or anything else)?

FWIW, the K9YC choke I used was about 6 turns of RG-6 wound through 4 or 5
*stacked* 2.4" Type 31 Fair-rite cores, *directly at the feedpoint*. Photos
linked to partway down the page at
http://www.w0btu.com/160_meters.html.

As you'll see, I'm an elevated radials man. Saves a lot of $ in radials
lying directly on the earth.

Also, please see
w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html

73, Mike
www.w0btu.com

On Mon, Jan 21, 2019, 7:46 PM Todd Goins <tgoins@gmail.com> wrote:

> Hello,
>
> Per many people's recommendations I added 800ft of radials today. That is 8
> x 100ft each.  It made a difference on the analyzer which I'll summarize
> below. It was dark when I finished but here are a few data points. I think
> it is better. The wide SWR curve still bothers me but the resistance is
> coming up.
>
> This is also using the new K9YC cookbook choke with 18 turns of RG400
> around a 2.4" type 31 toroid.
>
> The values are Freq, SWR, R, X, Z
>
> 1810  1.43  42.0  -14.5  44.5
> 1820  1.31  43.2  -10.7  44.5
> 1830  1.21  44.1  -6.7   44.7
> 1840  1.13  45.0  -2.5   45.1
> 1850  1.10  45.9  1.7   45.9
> 1860  1.14  47.0  5.7  47.3
> 1870  1.23  48.0  10.1  49.1
> 1880  1.34  49.1  14.7  51.2
>
> Any thoughts?  The 160 CW contest is only 4 days away, I don't have a lot
> more time to make changes but I could run a "few" more radials...
>
> 73,
> Todd - NR7RR
>
>
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