Same with the DDRR. It's official name is Directional Discontinuity
Ring Radiator, which was supposed to refer to how it "worked", but in
reality it's just a very short vertical antenna with a transmission line
wrapped in a circle to provide top loading. Like any other piece of
metal that you can manage to feed some power without blowing up your rig
it will radiate >something<, but the original explanation for it's
function was ridiculous.
Many of the purported descriptions for these small antennas and how they
function are frankly embarrassing for a hobby supposedly based in science.
73,
Dave AB7E
On 1/18/2017 11:10 PM, Jim Thomson wrote:
Date: Wed, 18 Jan 2017 11:19:35 -0500
From: K7LXC@aol.com
To: towertalk@contesting.com
Subject: [TowerTalk] [antenneX] Small and exotic antennas evaluated
Howdy, TowerTalkians --
You may be interested in these books.
Cheers,
Steve K7LXC
SMALL & EXOTIC ANTENNAS
A compendium of antenna evaluations. Learn the real performance from the
experts!
50 Chapters and 468-page book ready for immediate download.
This book provides excellent knowledge by experts about how antenna
technology has evolved over the past 20 years.
One look at the list of contents shows just how large of a void it fills
about the myriad of concepts to shrink the present antenna designs.
For more info:
http://www.antennex.com/Sshack/eval/eval.htm
### Superb. I had 3 x Isotrons when I was in the condo years ago,
80-40-20m. The only thing that radiates is the...feedline, typ 8 ft long.
Put a good balun on it, and it wont radiate at all, which is why they dont
recommend using a balun. Of Course CQ rag did a review on the isotron, and
had them hyped beyond max...installing them on a tall tower to boot...with a
200 ft feedline.
## Fractal ants, EH, etc, they are all junk. Cant wait to read the book
though,
it should be a good read. Even scientific american drank the fractal coolaid,
pure junk science.
## somebody did another book several years ago, how trapped ants actually
work,
esp trapped tribanders. Baffles me how wilson electronics managed to get a
hairpin
match to work on a 20-15-10m yagi. Mosley of course, introduces enough trap
losses,
such that the normal 20-25 ohm DE feedpoint Z, ends up being 50 ohms.
## our local radio inspector buys a TA-33 jr. His reason was... cuz it had a
dead flat swr.
He also found out....fast, that it was also a good 10 db down from a 204BA.
That same
33jr vs 204BA experiment has been done at least 8 times here in town..all
with the same results.
Jim VE7RF
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