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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