Topband
[Top] [All Lists]

Re: Topband: Short radials?

To: "DAVID CUTHBERT" <telegrapher9@gmail.com>
Subject: Re: Topband: Short radials?
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Thu, 27 Sep 2012 23:07:12 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I have no evidence that would lead me to  doubt the measurements of the
other bands.

160 meters measurenent:
15 ohm base R
2 ohm radiation resistance
5 ohm cool loss
8 ohm ground loss (rounded to 10)

This is the accepted procedure for measuring base referred ground loss, is
it not?

I used to think ground resistance always meant something, then I learned it didn't. I gave an example with a 40 meter system I tested.

Ground systems, even with buried radials, have standing waves. Standing waves change the impedance along the wire. It is possible to have a wide range of ground system contributed resistance at the base of the antenna for a given amount of loss.

Something is correct within what we will accept all the time, or it is not a reliable method.

I think N6RK or k6mhe found similar results, and I know my truck acts like much less resistance than actual losses indicate.

I think the ARRL Handbook or QST had something someplace where a fellow moved an 80 meter antenna to the center of a car and had 2 ohms ground loss. I thought, "Wow, I'll just park a car under my vertical. Not only will it be a good ground, I'll also have a status symbol as soon as a tree grows through the windows."

73 Tom
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

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