Ken,
I don't know if the low angle efficiency falls off faster than the high
angle radiation.
I can't remember ever reading that, but I have probably only read "a drop in
the bucket" of all there is.
I do know that I changed my attitude about verticals since reading Rudy's
papers.
I also know that there is no reason to ever use a vertical with inefficient
ground.
Instead I use a vertical dipole, 30 to 40 ft. overall length, fed in the
middle with openwire, and matched with a matchbox inside the shack.
No radials, yet still has fairly good efficiency.
I can't imagine why people continue to go with the traditional design,
except for the case that they are willing to lay down a complex ground
system (or 4 elevated radials per band).
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Ken Brown
Sent: Wednesday, January 05, 2011 12:09 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
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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