art wrote:
On 9 Oct, 19:35, John Smith wrote:
art wrote:
www.newswise.com/articles/view/532935
Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made
A$$'es out of all the "experts" and continues to do so ... sometimes
there is real justice.

Regards,
JS

Yup, the experts were not experts after all just phony's.
Ofcourse we now have to wait for comments like " I knew that all the
time",
"I have been using that method for years", "that was invented by
Mantovani
a hundred yeard ago but he just didn't get around to printing it"
Art


The patent, US 7187335, is a real hoot. I especially like the part where
he describes doubling the bandwidth by adding a parasitic winding
intertwined with the base coil helix.

Do you suppose his antenna is in equilibrium? Could proper application
of Artsian-Gaussian theory improve it even more?



73,
Gene
W4SZ

On 10 Oct, 10:47, Gene Fuller wrote:
art wrote:
On 9 Oct, 19:35, John Smith wrote:
art wrote:
www.newswise.com/articles/view/532935
Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made
A$$'es out of all the "experts" and continues to do so ... sometimes
there is real justice.

Regards,
JS

Yup, the experts were not experts after all just phony's.
Ofcourse we now have to wait for comments like " I knew that all the
time",
"I have been using that method for years", "that was invented by
Mantovani
a hundred yeard ago but he just didn't get around to printing it"
Art

The patent, US 7187335, is a real hoot. I especially like the part where
snip
Do you suppose his antenna is in equilibrium? Could proper application
of Artsian-Gaussian theory improve it even more?



73,
Gene
W4SZ- Hide quoted text -

- Show quoted text -

Gene, you are just showing your ignorance of physics.
What is it about the word "equilibrium" that you can't understand?
How on earth can you say you are educated in physics?
How is it that you do not have an understanding of Gauss?
Or are you trying to be funny with the word "Artisian-Gaussian"
like the rest of your fellow school boys?
What manner of man are you trying to project of yourself to other
readers of this group, a comedian or an ignoramous or somebody with
senior moments in
continuos series? You never seem to have anything to say that is
informative so why the need to draw attention to yourself.
What is missing in your life such that you have to mimic a fool that
want's to be funny in the absence of a education of any sort?
Back to the Vincent antenna, he has designed an antenna that is
shorter
than that known before. You didn't come up with it he did. He has a
patent
based on his claims and not for the introductory writing.An engineer
in automobiles
has shown interest in it where you have never gained outside interests
in any thing
you have done in your life time. The input impedance is an advantage
over similar antennas
and at the same time not requiring a ground plain without being a
problem to the transmitter.
He is also radiating well in comparison to the height of antenna and
the
radiating system has the appearance of being efficient. Vincent has
come up with something new
and because of the 'not invented in my backyard' you want to diminish
his achievements.
But you can't diminish his achievments without providing an
engineering analysis
and for that you do not have the necessary education.
Maybe it is better that you continue to mimic a fool that wants to be
funny but
better to become a succes at that at home before showing off your
skills in public
even tho you are getting laughter, not with you but at you.
Art
Art

"art" wrote
Back to the Vincent antenna, he has designed an antenna that is
shorter than that known before. .... The input impedance is an
advantage over similar antennas and at the same time not
requiring a ground plain without being a problem to the transmitter.
He is also radiating well in comparison to the height of antenna and
the radiating system has the appearance of being efficient.
___________

Probably you'll agree that good, new antenna designs need more
than "the appearance of being efficient." Let's expand on this..

The link below leads to a calculation of the system radiation efficiency and
r-f bandwidth of a conventional, 30-degree, base-loaded monopole, using the
equations found in standard antenna engineering texts. This is the physical
height used for the "standard DLM" antennas tested by the Navy for the
University of Rhode Island. The coil and r-f ground loss was set to 2 ohms,
total, to approximate the conditions in the U-RI test.

This non-DLM configuration of a short monopole has a system radiation
efficiency of about 59%, and for 1 kW of applied power generates an inverse
distance groundwave field of 241 mV/m at 1 km.

A standard, 1/4-wave vertical monopole with a matching network and r-f
ground loss of 2 ohms, total, is about 95% efficient, and for 1 kW of
applied power generates an inverse distance groundwave field of about 306
mV/m at 1 km.

So the field of the 30-degree radiator is about 2.07 dB below that of the
90-degree radiator -- and that is due mostly to the much lower radiation
resistance of the 30-degree radiator (about 2.9 ohms vs about 36 ohms)
against the 2 ohms of other losses in each system.

The March 31, 2005 U-RI test report states that the 3.5 MHz standard DLM had
a measured groundwave field at 1 mile that was 2.33 dB less than the Navy's
reference monopole (whose electrical height is not stated, but presumably is
90 degrees). So the measured h-plane gain of that DLM was about 0.26 dB
_less_ than a conventional, base-loaded, 30-degree monopole -- although that
difference could be within the range of measurement and/or modeling error.

Also note, Art, that the DLM needs a good r-f ground, just as do all
monopoles, and especially short ones. The Navy went to great effort to
provide a very good r-f ground and propagation path for the range where the
DLM was tested.

http://i62.photobucket.com/albums/h8...rtMonopole.gif

RF

Gene Fuller wrote:

...
The patent, US 7187335, is a real hoot. I especially like the part where
he describes doubling the bandwidth by adding a parasitic winding
intertwined with the base coil helix.

Do you suppose his antenna is in equilibrium? Could proper application
of Artsian-Gaussian theory improve it even more?



73,
Gene
W4SZ

What? You don't see cutting the capacitance between winding turns as
causing some measurable effect which in turn affects a property of the
antenna proper?

Thicker conductor(s) usually means a measurable gain in bandwith, with a
parasitic element in such close proximity to the major element, a gain
in bandwidth is not that difficult to propose and attempt to prove/disprove.

Regards,
JS

John Smith wrote:
Gene Fuller wrote:

...
The patent, US 7187335, is a real hoot. I especially like the part
where he describes doubling the bandwidth by adding a parasitic
winding intertwined with the base coil helix.

Do you suppose his antenna is in equilibrium? Could proper application
of Artsian-Gaussian theory improve it even more?



73,
Gene
W4SZ

What? You don't see cutting the capacitance between winding turns as
causing some measurable effect which in turn affects a property of the
antenna proper?

Thicker conductor(s) usually means a measurable gain in bandwith, with a
parasitic element in such close proximity to the major element, a gain
in bandwidth is not that difficult to propose and attempt to
prove/disprove.

Regards,
JS

John,

The effects you mention may have some impact on bandwidth, but they
don't double it. And the capacitance probably increases, not decreases.
Placing an extra conductor between two capacitor plates increases the
capacitance. At the same time placing a grounded shield between two
capacitor plates reduces or eliminates the coupling between the original
plates. It is not clear to me which effect would dominate in this case.
In either case it is unlikely to be very important.

Lots of people understand how to make an antenna broadband; simply add
resistance. This is not always "bad". It is merely a choice.

Just for grins I did a little EZNEC experiment. I started with a base
loaded monopole that used a generated helix as the loading coil. I
adjusted and resonated the system to SWR = 1 and took a look at the
bandwidth. I arbitrarily took SWR = 2 as the bandwidth limits. I then
added a parasitic winding between the turns of the helix. This winding
was not connected to anything. I reran the simulations.

What I found was interesting, but not surprising.

When the wires were treated as lossless, there was virtually no
difference in bandwidth or any other parameter. The parasitic winding
had essentially no impact.

When I changed the wires to copper, the bandwidth increased in both
cases. However, in the case with the parasitic winding the new bandwidth
was 2.5 times as large as the case without the extra winding. The
resonant input impedance was also about 2.5 times larger.

There is only one plausible explanation for this observation. The
parasitic winding adds loss to the antenna system. I won't claim this is
"bad". Depends on the characteristics desired.

The bottom line is that there is no wondrous invention here. Either
Vincent knew about this effect and chose to ignore it, or he did not
understand what was happening. The capacitance explanation is just baloney.

73,
Gene
W4SZ

Gene Fuller wrote:

...
73,
Gene
W4SZ

Well, OK. Post your EZNEC modeling mockup of the antenna and we'll
check it out ... :-)

JS

Gene Fuller wrote:
. . .
What I found was interesting, but not surprising.

When the wires were treated as lossless, there was virtually no
difference in bandwidth or any other parameter. The parasitic winding
had essentially no impact.

When I changed the wires to copper, the bandwidth increased in both
cases. However, in the case with the parasitic winding the new bandwidth
was 2.5 times as large as the case without the extra winding. The
resonant input impedance was also about 2.5 times larger.

There is only one plausible explanation for this observation. The
parasitic winding adds loss to the antenna system. I won't claim this is
"bad". Depends on the characteristics desired.

You can easily verify this by noting the change in gain as the extra
winding is added and deleted. You should also see a corresponding change
in feedpoint resistance, assuming that the extra winding doesn't change
the current distribution. A couple of additional interesting experiments
would be:

1. Increase the loss of the coil in a model without the extra winding
until the gain is the same as the model with copper loss and no extra
winding. Then see how the bandwidth compares to the original model with
extra winding.

2. Instead of increasing the loss of the coil, add a resistor to the
base of the copper loss non-extra winding antenna and adjust it so the
gain is the same as for the model with copper loss and extra winding.
How does the bandwidth compare to the original model with the extra winding?

The bottom line is that there is no wondrous invention here. Either
Vincent knew about this effect and chose to ignore it, or he did not
understand what was happening. The capacitance explanation is just baloney.

I'm afraid that's probably true. With antennas, you can choose any two
of efficient, and broadband, and electrically small. This antenna claims
all three, so I'm very skeptical.

Roy Lewallen, W7EL

On Oct 11, 4:25 pm, Roy Lewallen wrote:
Gene Fuller wrote:
. . .
What I found was interesting, but not surprising.

When the wires were treated as lossless, there was virtually no
difference in bandwidth or any other parameter. The parasitic winding
had essentially no impact.

When I changed the wires to copper, the bandwidth increased in both
cases. However, in the case with the parasitic winding the new bandwidth
was 2.5 times as large as the case without the extra winding. The
resonant input impedance was also about 2.5 times larger.

There is only one plausible explanation for this observation. The
parasitic winding adds loss to the antenna system. I won't claim this is
"bad". Depends on the characteristics desired.

You can easily verify this by noting the change in gain as the extra
winding is added and deleted. You should also see a corresponding change
in feedpoint resistance, assuming that the extra winding doesn't change
the current distribution. A couple of additional interesting experiments
would be:

1. Increase the loss of the coil in a model without the extra winding
until the gain is the same as the model with copper loss and no extra
winding. Then see how the bandwidth compares to the original model with
extra winding.

2. Instead of increasing the loss of the coil, add a resistor to the
base of the copper loss non-extra winding antenna and adjust it so the
gain is the same as for the model with copper loss and extra winding.
How does the bandwidth compare to the original model with the extra winding?

The bottom line is that there is no wondrous invention here. Either
Vincent knew about this effect and chose to ignore it, or he did not
understand what was happening. The capacitance explanation is just baloney.

I'm afraid that's probably true. With antennas, you can choose any two
of efficient, and broadband, and electrically small. This antenna claims
all three, so I'm very skeptical.

Roy Lewallen, W7EL- Hide quoted text -

- Show quoted text -

Maybe it not the wire but the insulation on the wire, A little
dielectric heating would surely make it more broadbanded.


Jimmie