So you're sayin' it was luck....
-----Original Message-----
From: Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>
To: 'Discussion of Ten-Tec Equipment' <tentec@contesting.com>
Sent: Wed, Sep 23, 2015 7:28 am
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?
Yes.
It wasn't actually "resonant" on 160 but it worked on 160.
You saw a reasonable SWR on that band.
First of all, one of the biggest causes of disagreement on any topic is a
lack of agreement on the meaning of key words.
"Work" can be interpreted in many ways.
My favorite knock off on this word it to point people to the July 2000 QST
article (page 47) written by N6BT, "Everything Works." In that article, Tom
tells us how he worked all continents on a single weekend, using a 100w
light bulb mounted on a 6' high fence post as an antenna. He used a 1:1 RF
choke near the bulb to make sure the coax wasn't radiating.
That file is in the QST archives online and can be downloaded from there,
and I have occasionally found links to it online, though a quick google
right now didn't produce anything.
My box spring mattress "works" on 160m when I used a matchbox. As a kid I
attached my Johnson Viking Matchbox to my bed springs and worked NYC getting
a 579 report. I was located in Oklahoma. EVERYTHING WORKS.
In your case, it is either the transmission line working as the antenna and
the antenna acting as top loading - or you had transmission line
transformation causing the match in the shack to "look good". If you had
measured at the balun, I'm sure you would have found the SWR to be terrible.
This happens often. Understand, I've probably measured around 40 different
OCFD antennas and every now and then I see a huge dip near 160m. It would
only take a bit of adjustment to get that dip into the band. But as I said,
it's not a real point of resonance, just a point that has low enough SWR
that your transmitter will send power its way. How much power is actually
radiated is anyone's guess but as we all know, we can work the world on 5w,
so even if just 5w gets radiated, it works.
If anyone has a better explanation, I'm all ears.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Joe
Papworth via TenTec
Sent: Wednesday, September 23, 2015 12:21 PM
To: tentec@contesting.com; k3ndm@comcast.net
Cc: k8mp@aol.com
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is
gest?
Great stuff Rick. I am officially anointing you as the Go-to Guy on Windoms
and their history.
Maybe you can explain why an ocf antenna I once had worked on 160. I called
it "My accidental 160 meter antenna."
It was a full wave on 40, (i.e. 130 ft) and fed with coax, 1/4 wave in from
one end. I intended to use it only on 40 but I discovered it was resonant on
160 also.
Any idea why it worked? Or was it just pure luck?
Thanks, Joe, K8MP
Sent from AOL Mobile Mail
-----Original Message-----
From: Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>
To: 'Barry LaZar' <k3ndm@comcast.net>; 'Discussion of Ten-Tec Equipment'
<tentec@contesting.com>
Sent: Wed, Sep 23, 2015 03:55 AM
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is
gest?
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<pre style="font-size: 9pt;"><tt>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
[<a
href="mailto:tentec-bounces@contestin'mailto:tentec-bounces@contesting.com?">mailto:tentec-bounces@contestin
g.com</a>] On Behalf Of Barry LaZar
Sent:
Wednesday, September 23, 2015 1:04 AM
To: <a
href="tentec@contesting.commailto:tentec@contesting.com">tentec@contesting.com</a>;
<a href="Rick@DJ0IP.demailto:Rick@DJ0IP.de">Rick@DJ0IP.de</a>
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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