ARRL Antenna Books have covered this for a long time. The 21st Edition (latest)
on page 6-16 (index says 6-20, but that's incorrect), says:
"Work by Al Christman, K3LC (ex-KB8I) has shown that 4 to 8 elevated radials
can provide performance comparable to 120 " 1/4 wavelength "long buried wires."
That pretty much says it all. After all, that's what we do when we solder wires
to an SO-239 to make a 2-meter ground plane.
Dave
WA3F
----- Original Message -----
From: "John Graves" <jh.graves@verizon.net>
To: tentec@contesting.com
Sent: Wednesday, January 5, 2011 4:20:56 PM
Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
I have had until recently, an R7 that worked almost anywhere I wanted
to try, but if you want to talk 1.4 wave verticals, I would thing you
want to start with Severns article in QST (In 2000). Also wasn't there
an earlier article recarding vertical ground systems by Sommers or
Somers? Anyway, The conclusion I drew from them is that traditional
ground systems are fine but if you are going to compromise, then a lot
of short radials are better than a few long ones. I can't remember the
author but there was another article (maybe by one of the two authors I
cited) that claimed the big exception is for elevated radials. The
article claimed (as I recall) that 4 elevated radials performed as well
as 32 ground radials. In either case, it sounds as though there are
several options available to us vertical users that make for a better
than average antenna system
John -- WA1JG
WA1JG@nsradio.org
On 1/5/2011 12:42 PM, Richards wrote:
> There is a question or two on the Extra Class Exam
> that makes the same point. You add ground radials to
> to a quarter wave vertical antenna to increase low radiation
> angle. Gordon West says so on his audio discs.... ;-)
>
> ================= JHR ===================
>
> On 1/5/2011 12:09 AM, Ken Brown wrote:
>> Hi Rick,
>>
>> I'll have to review this, maybe I am suffering from a false memory, or
>> an accurate memory of false information. I thought that a poor
>> counterpoise under a vertical reduced the overall efficiency AND had a
>> negative effect on the pattern diminishing the low angle radiation more
>> than the higher angle radiation. N6LF's studies may help clear it up.
>>> The number of radials won't really affect the angle of radiation.
>>> With a poor ground, you will still have a low take-off angle; you'll just
>>> had a heck of a lot of ground losses.
>>>
> ================================================
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