Topband: Elevated vs Buried Radials

[Bill Tippett]

N9ADG wrote:
 >How can we correlate "good" and "poor" soil qualities
to the US gov't survey (mentioned in previous postings
to this list)? I envy the "30" and even the "16"
areas, being in a "4".

	"Very Good": conductivity = 30 mS/m, dielectric constant = 20.
	"Average":  conductivity = 5 mS/m, dielectric constant = 14.
	"Very Poor":  conductivity = 1 mS/m, dielectric constant = 5.

NH6KB wrote:
 >Thanks for the information. I don't get NCJ, so could you fill in a
couple of details? Does all of this information assume a full quarter
wavelength vertical above the radial system? And this is for 1.8 MHz?

	Modeling data is for a full size 1/4 wl vertical.  40/80/160 are
covered in the article but the data I posted was for 160 only.

 >I have very good ground conductivity in my yard. If I had radials 10'
off the ground, my inverted L would then have only a 30' vertical
section instead of 40'. I would like to know if the improvement from
using raised radials would be offset by the reduction in efficiency of
having a shorter vertical portion in my inverted L.

	That could only be answered by modeling, but based on
Fig 10 in the second article, I would guess you are better off with
your 40' vertical assuming you already have a decent radial system
(at least 30 radials).

	For those of you who are not NCJ subscribers, you might
want to consider it even if you are not a contester.  It is now the
only publication I subscribe to besides QST which is "free" since
I'm a lifetime member.  Cost is only $20 per year and Carl K9LA
is doing an excellent job of editing it.  Check it out here:

	http://www.ncjweb.com/

					73,  Bill  W4ZV

http://www.ncjweb.com/