Milt Jensen, N5IA (SK) constructed his original (circa 1990s) 160M station TX
antenna based on a similar design I encouraged him use. He built a 180 ft tower
with an insulator at 50 ft, Four elevated quarter wave radials, each made of a
box of four pieces of # 12. This was on his "city" lot where buried radials
were impossible
It worked very well, We did not have the tools to make real field strength
measurements to compare to a model, but on air performance was excellent
It worked well enough for him to use the concept in several similar
installations and to make his 8 circle array
The radial height above ground clearly did not need to be 50 feet,. It did need
to be high enough to easily be well above a tall truck, or more commonly, a
horseback rider.
We used a single element elevated radial 160M TX antenna, and for the 80M 4
square at XZ0A with considerable success.
The concept of exciting a tower from the inside is very interesting. The
reposting this article a has me thinking about one situation I have available to
me that can not have a complex installation outside the general dimensions of
the tower (large but not tall)
One thing to bear in mind throughout any analysis of such designs for 160M is
that the total focus of the Broadcast designs and measurements and proofs is
energy at zero degrees elevation. Our needs benefit from low angle radiation,
for certain, but, little attention is paid by the broadcasters and by the
modeling programs to position and shape of elevated lobes, or for that matter,
the shape of the main lobe above zero elevation
Robin Critchell, WA6CDR
----- Original Message -----
From: "Ken WA8JXM" <wa8jxm@gmail.com>
To: "Radio KH6O" <radio.kh6o@gmail.com>
Cc: "topband" <topband@contesting.com>
Sent: Thursday, January 04, 2024 20:56
Subject: Re: Topband: Using 4 - 6 elevated radials in lieu of 120 buried wires
Very interesting, thanks for sharing.
I have seen similar information in one of the ARRL manuals, that elevated,
insulated radials are more efficient than the typical ham buried 30 or 40
radials Perhaps that originated from the information you posted.
Is it okay if I post your information to a ham antennas group?
Ken WA8JXM
On Thu, Jan 4, 2024 at 9:58 PM Radio KH6O <radio.kh6o@gmail.com> wrote:
Attached is an interesting research paper by Clarence Beverage.
--
73,
Jeff KH6O
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