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Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?

To: "Rick - DJ0IP / NJ0IP" <Rick@dj0ip.de>, "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?
From: "Barry LaZar" <k3ndm@comcast.net>
Reply-to: Barry LaZar <k3ndm@comcast.net>, Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Wed, 23 Sep 2015 14:00:12 +0000
List-post: <tentec@contesting.com">mailto:tentec@contesting.com>
Rick,
I stand corrected. That is a great piece of research. All of what I knew of the Windom was from material from the ARRL and early material from CQ which credited Windom with the original work. However, we, the ham community, still call an off center fed dipole a Windom and accept it as a multiband affair.

Until recently, there had been no consideration for impedance; radios up until ~the early 1950's had wide enough impedance matching abilities to not make this too big an issue. However, with the advent of coax and it's acceptance, this became a problem. Hence, the look back for ways to make a multiband antenna, an impedance bounded antenna. The "Windom" was one that could fit the bill as you could find a feed point that allowed matching to a coax feed. And yes, I am aware of some interesting schemes other than coax. Unfortunately, the affects of high SWR on a voltage type balun transformer weren't as widely known as they are today. That led to RF in many a shack. we have a better understanding of the phenomenology today so it isn't as big an issue.

There have been many who have played with single wire antennas. The group/ham club that created the variant called the Carolina Windom is one. They actually deliberately caused a portion of the feed line to radiate. It's my main antenna and it does a pretty good job. Was it the only way to go? Probably not when you consider some of the other approaches out there. I argue that antennas are for hams what anchors are for sailors, a basis for deep meaningful disagreement. However, I do stand by my position that a 1/2 wave on the lowest operating frequency that you can feed successfully makes a pretty good general purpose antenna.

73,
Barry
K3NDM

------ Original Message ------
From: "Rick - DJ0IP / NJ0IP" <Rick@dj0ip.de>
To: "'Barry LaZar'" <k3ndm@comcast.net>; "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Sent: 9/23/2015 3:54:48 AM
Subject: RE: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?

Good Morning Gang,

Indeed there is some historical perspective missing:

...1.  Loren Windom did not invent the Windom
...2.  The Windom was NOT designed to be a multi-band antenna
...3.  It definitely NEVER was fed at the 1/3 point

Everything Barry write below that I agree with.

Guys, there is no need to guess at this stuff.
MOST of it was written up in QST and ALL of it is online in the ARRL
archives to read.
I will list some of them at the bottom of this email.


...1. The Windom, named after Loren Windom, was the result of a two part studies/paper as a project in order to obtain a college degree (from Ohio
State University).

Part 1: was led by John Byrne (W)8DKZ, together with Ed Brooke (W)8DEM -
1925/26

Part 2: was led by John Byrne, together with A. Crawford (was also a ham but
I can't find/remember his call sign) - 1927/28

There was actually a Part 3: where Byrne turned the project over to John
Ryder W8DQZ. I could not find any information on what Ryder did.

The (assistant) Professor overseeing the project was William Everitt.
Loren Windom (W)8GZ was best friends with John Byrne and together they built one of the hottest ham radio stations at the time. It was on the air as 8GZ (later W8GZ) running 250w, which at the time was considered as a "California
Kilowatt" is today.

The projects goal was to find a better way to feed a Herz antenna.
You see, these guys were having similar problems we "enjoy":  RF in the
Shack and feedline radiation.

Loren Windom and others felt they could find a sweet spot to [single wire] feed the Herz where the feedline would not radiate. Windom failed to find
this point, but later Byrne and Co. found it.

Windom himself had been working on this a few years earlier and gained fame
from his own research work.  You can read details of his research and
(flawed) results in a July 1926 QST article written by Robert Kruse, the QST
Technical Editor at the time.  The article, entitled "Feeding Antennas"
begins on page 8 and Windom's work is described on page 11.

The professional paper on this research work was published in the IRE in October of 1929, one month after Windom's QST article. The IRE article had
been submitted first but took longer to get published.  That's why many
people think Windom was the creator, when indeed he begins his paper by
clearly stating that it is not his work but rather the work of John and
others (listing them all).
Everitt's name also appeared on the IRE paper, listed first as it was
tradition to list the Professor's name on papers written by students. As a result, many people credit Everitt as being the true inventor of the Windom.

To be fair, IMO they all as a team are the joint inventors. Windom (a law student and later lawyer) and Everitt were out in the field assisting during
lunch breaks and evenings.


...2.  "RADIATION-FREE FEEDLINE OF A HERZ ANTENNA" (on its fundamental
frequency) was the goal of the Windom. There was no attempt to find a
harmonic antenna.
A radiation-free feed point was indeed found, but not by Windom.  The
antenna was named after Lorem by a twist of luck.

A Windom (antenna) was a very special, very narrow-banded antenna.
However without Internet and few people having telephones in the 1920s,
information was spread by other means - mostly on the air in the ham
community. The original concept was not understood and that part of the
story was dropped.

People begin building this antenna (as described in an article Loren wrote
on page 19 of the September 1929 QST) and then began "improving" it.

They tried it on harmonic bands. It worked. Worked? Yes they made QSOs but it wasn't working as a Windom, it was working as something in between a "T" and "Inv.-L" antenna, as described in detail by John Nagle, K4KJ in the May issue of HR. I won't elaborate here. You can read the article if you want
to know more.

I personally built this harmonic version in 1963, right after moving from
Germany to Oklahoma.  I was the new kid on the block and didn't know
anybody.  Within one week of erecting my "Windom", I had met all of my
neighbors!  (hi)
Yes, I too called it a Windom, even though it was not the original as Byrne
and Co. had defined.

...3. As I stated in an earlier email, a feedpoint was found but not at the 1/3 mark. It was found to be in a formula with a coefficient with respect to the diameter of the wire. The coefficient was defined for two wire sizes as the feed point position "D", in terms of feet from one end of the aerial.
It was defined as (Length of Aerial in ft.) x (Coefficient) / 180.

For #14 wire, the coefficient was defined as "25".
For #24 wire, the coefficient was defined as "30".
The wire itself was a one half wavelength Hertz.
As you see, there was no mention of "1/3" anywhere in the Windom paper or
the professional IRE paper.

On a side note, Harmonic Resonance was found to be 2.07 x Fundamental.
So a Herz cut for 3.500 MHz would be resonant on 7.245 MHz.

Higher harmonics were resonant outside of the band.
Using the antenna that far off resonance resulted in strong feedline
radiation.
This was exactly the thing the Windom concept was trying to eliminate.
So any contention that a Windom antenna is a harmonic antenna is false.

However, the beast that hundreds of hams were using as a harmonic antenna in the 1930s was being called a Windom, when indeed, according to K4KJ (see
article) was in reality just a bent longwire.

As we all know, a longwire antenna can be used on harmonic bands. It also needs radials or a counterpoise; the coax-fed OCFD does not. These are two
entirely different antennas.

Over the years the saga has been modified and few people have any idea what these pioneers actually did with the minimalistic means they had to work with. I found it fascinating researching this topic and for those of you
who are also interested, here is a list of interesting reading:

..> "The Hertz Antenna at 20 and 40 Meters" by Howard Williams, (W)9BXQ -
QST, July, 1925 p.24.

..> "Feeding the Antenna" by Robert Kruse - QST, July, 1926 p.8.

..> (Original Windom Paper) "Notes on Ethereal Adornments", by Loren Windom,
(W)8GZ - QST, September, 1929 p.19

..> "The Windom", by Drayton Cooper, W4WXY - 73 Magazine, July, 1962 p.34

..> "Further on; The Windom" by W3AFM - 73 Magazine, August, 1963 p.76 NOTE: At the bottom of that document you will find a list of 13 related articles from various sources, dating back to the late 20's and up to 1962.

..> "Windom Antennas" by John Nagle, K4KJ - ham radio magazine, May, 1978 p.
10

ENJOY!

73 - Rick, DJ0IP
(Nr. Frankfurt am Main)

-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Barry LaZar
Sent: Wednesday, September 23, 2015 1:04 AM
To: tentec@contesting.com; Rick@DJ0IP.de
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is
gest?

I think there is some historical perspective that is missing in some our discussions. First open wire was used in the early days of radio as there wasn't much else around. You could run a wire from your antenna directly to your transmitter's output, but there were really few other ways to go. Coax came into being somewhere around 1940, and this can be disputed, for the purpose of running a transmission line through a ship's steel bulked. The 50 Ohm number came about because that is what resulted from the material at
hand, or you can supply another story.


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