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Old December 22nd 10, 02:13 PM posted to rec.radio.amateur.antenna
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Default Fractal Sleeve for Monopoles?

FOR DISCUSSION...

YouTube video on this subject at
http://www.youtube.com/watch?v=QWd0n...layer_embedded

The comments in italics were posted on another website, which prompted
my five points that follow. Thought they might be of interest here.

It would be interesting to learn if the results and conclusions shown
in the
YouTube video have been confirmed from complete documentation by
an independent test lab.

but i have another idea that has come out.might be a game changer
check this out. i have been researching this and it could be the
breakthrough we need. a broad band antenna, no loading coil needed,
double the eirp!


Observations from watching the YouTube video...

1. A 1/4-wave monopole was used in the test. A 1/4-wave monopole is
self-resonant, so no loading coil was necessary. However it would be
necessary
for the electrically short monopoles permitted for unlicensed Part 15
AM, and
would still be needed if the FCC changed 15.219(b) to allow a 30'
"ground"
conductor.

2. A 1/4-wave monopole driven against a perfectly conducting ground
plane such
as shown in this video has a peak system gain of about 5.15 dBi. The
video
shows a resonant gain for that monopole system without the sleeve as
"1 dBi"
referenced to the gain of a log periodic antenna.

However by definition the term dBi means decibels with respect to an
isotropic
radiator, and a log periodic antenna definitely is not an isotropic
radiator.
The gain units used in the video are therefore unconventional, and
need further
definition.

3. The relative field radiated by a conventional 1/4-wave vertical
monopole
driven against a perfectly conducting ground plane always is maximum
in the
horizontal plane. Such a system radiates virtually 100% of the matched
power
applied to its input terminals.

Therefore the peak gain of that antenna system at resonance cannot be
improved
by putting a sleeve of any kind on the monopole.

The sleeve may change the shape of the radiation pattern of the system
without
the sleeve, though, which could change the field intensity at the
location of
the receiving antenna used in the test. This could account for the ~3
dB
improvement shown in their results when using the sleeve.

4. Nothing is shown in the video about the amount of matched power at
the
feedpoint with and without the sleeve. If that is not held constant
then the
test will be flawed.

5. The VSWR bandwidth of a monopole may be increased simply by using a
larger
cross-section conductor of "non-fractal" construction.
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Old December 22nd 10, 05:16 PM posted to rec.radio.amateur.antenna
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Default Fractal Sleeve for Monopoles?

On Dec 22, 8:13*am, Richard Fry wrote:
FOR DISCUSSION...

*YouTube video on this subject at
*http://www.youtube.com/watch?v=QWd0n...layer_embedded


Was the video narrated by Phil?
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Old December 22nd 10, 09:51 PM posted to rec.radio.amateur.antenna
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Default Fractal Sleeve for Monopoles?

On Dec 22, 10:16*am, Bill wrote:
On Dec 22, 8:13*am, Richard Fry wrote:

FOR DISCUSSION...


*YouTube video on this subject at
*http://www.youtube.com/watch?v=QWd0n...layer_embedded


Was the video narrated by Phil?


I just watched the video one time and it diddn't sound like Chip to me
not that it matters.
He is comparing to a log periodic as it is non frequency dependent.
When he placed a sleeve over the 1/4 wave it was fed I presume by
capacitive coupling not that it really matters tho capacitive coupling
does help with band extension and constant SWR. He first started with
a circular sheet as a radiator over which he placed a second circular
sheet that is perforated or mesh design.
A mesh design when fed acts like a closed circuit helical where the
current applied takes little interest in the vertical connections so
it to is non frequency dependant the same as the
log style antenna. The mesh current flow is a initial spurt of full
current which then degrades to zero when it get back to the starting
point after at least a single wavelength of travel, not a quarter
wave. Ifg the frequency applied is of many wavelengths it will then
display a near constant SWR over a extended frequency of which there
have been many studies available to confirm. Again if their are enough
wavelengths are present it gets to a equilibrium point of resonance
which includes the overshoot of the applied current. I say resonant
because he is not using fractional wavelength dimensions which are all
floating dimensions where a period (full wave) is not. The overshoot
of applied current increases as much as 5 times, so with the increase
in current it is easily seen that as the current goes so does the
radiation. One could turn around the whole experiment as one of a
radiator inside a Faraday cage which is also used as proof of
reciprocity with respect to radiation from a radiater that is in
equilibrium. Thus it is exactly the same as what I have been proposing
for many years which stems from the Gaussian extension to Maxwells
equation.
I have just completed a similar antenna made as a flat solenoid
without a plunger sometimes referred to as a Meander or pancake
antenne.
It is close to 40 inches dia with a hieght of !/2"
My expectations is that when placed inside a faraday shield, an
example of the Gauss extension it will have a resonance of at least 10
metres down to 160 metres with a SWR less than 3: 1 and an applied
impedance of 50 ohms.
I was told that I had a patent on this if I paid publishing cost,
acceptance fees and to follow maintanance fees which I declined due to
the
high costs.
Best regards to all
Art Unwin
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Old December 24th 10, 05:15 AM posted to rec.radio.amateur.antenna
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Posts: 625
Default Fractal Sleeve for Monopoles?

On Dec 22, 9:13*am, Richard Fry wrote:
FOR DISCUSSION...

*YouTube video on this subject at
*http://www.youtube.com/watch?v=QWd0n...layer_embedded

The comments in italics were posted on another website, which prompted
my five points that follow. *Thought they might be of interest here.

It would be interesting to learn if the results and conclusions shown
in the
YouTube video have been confirmed from complete documentation by
an independent test lab.

but i have another idea that has come out.might be a game changer
check this out. i have been researching this and it could be the
breakthrough we need. a broad band antenna, no loading coil needed,
double the eirp!


Observations from watching the YouTube video...

1. A 1/4-wave monopole was used in the test. A 1/4-wave monopole is
self-resonant, so no loading coil was necessary. However it would be
necessary
for the electrically short monopoles permitted for unlicensed Part 15
AM, and
would still be needed if the FCC changed 15.219(b) to allow a 30'
"ground"
conductor.

2. A 1/4-wave monopole driven against a perfectly conducting ground
plane such
as shown in this video has a peak system gain of about 5.15 dBi. The
video
shows a resonant gain for that monopole system without the sleeve as
"1 dBi"
referenced to the gain of a log periodic antenna.

However by definition the term dBi means decibels with respect to an
isotropic
radiator, and a log periodic antenna definitely is not an isotropic
radiator.
The gain units used in the video are therefore unconventional, and
need further
definition.

3. The relative field radiated by a conventional 1/4-wave vertical
monopole
driven against a perfectly conducting ground plane always is maximum
in the
horizontal plane. Such a system radiates virtually 100% of the matched
power
applied to its input terminals.

Therefore the peak gain of that antenna system at resonance cannot be
improved
by putting a sleeve of any kind on the monopole.

The sleeve may change the shape of the radiation pattern of the system
without
the sleeve, though, which could change the field intensity at the
location of
the receiving antenna used in the test. This could account for the ~3
dB
improvement shown in their results when using the sleeve.

4. Nothing is shown in the video about the amount of matched power at
the
feedpoint with and without the sleeve. If that is not held constant
then the
test will be flawed.

5. The VSWR bandwidth of a monopole may be increased simply by using a
larger
cross-section conductor of "non-fractal" construction.


The whole video sounded like a lot of verbal sleight of hand to me.
Its a shame techs and engineers are not secure enough in their
knowledge to recongnize BS when they hear it and report it as such.
"The Emperor's New Antenna".

Jimmie

Jimmie
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Old December 24th 10, 03:27 PM posted to rec.radio.amateur.antenna
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Posts: 329
Default Fractal Sleeve for Monopoles?

On 24 dic, 05:15, JIMMIE wrote:
On Dec 22, 9:13*am, Richard Fry wrote:



FOR DISCUSSION...


*YouTube video on this subject at
*http://www.youtube.com/watch?v=QWd0n...layer_embedded


The comments in italics were posted on another website, which prompted
my five points that follow. *Thought they might be of interest here.


It would be interesting to learn if the results and conclusions shown
in the
YouTube video have been confirmed from complete documentation by
an independent test lab.


but i have another idea that has come out.might be a game changer
check this out. i have been researching this and it could be the
breakthrough we need. a broad band antenna, no loading coil needed,
double the eirp!


Observations from watching the YouTube video...


1. A 1/4-wave monopole was used in the test. A 1/4-wave monopole is
self-resonant, so no loading coil was necessary. However it would be
necessary
for the electrically short monopoles permitted for unlicensed Part 15
AM, and
would still be needed if the FCC changed 15.219(b) to allow a 30'
"ground"
conductor.


2. A 1/4-wave monopole driven against a perfectly conducting ground
plane such
as shown in this video has a peak system gain of about 5.15 dBi. The
video
shows a resonant gain for that monopole system without the sleeve as
"1 dBi"
referenced to the gain of a log periodic antenna.


However by definition the term dBi means decibels with respect to an
isotropic
radiator, and a log periodic antenna definitely is not an isotropic
radiator.
The gain units used in the video are therefore unconventional, and
need further
definition.


3. The relative field radiated by a conventional 1/4-wave vertical
monopole
driven against a perfectly conducting ground plane always is maximum
in the
horizontal plane. Such a system radiates virtually 100% of the matched
power
applied to its input terminals.


Therefore the peak gain of that antenna system at resonance cannot be
improved
by putting a sleeve of any kind on the monopole.


The sleeve may change the shape of the radiation pattern of the system
without
the sleeve, though, which could change the field intensity at the
location of
the receiving antenna used in the test. This could account for the ~3
dB
improvement shown in their results when using the sleeve.


4. Nothing is shown in the video about the amount of matched power at
the
feedpoint with and without the sleeve. If that is not held constant
then the
test will be flawed.


5. The VSWR bandwidth of a monopole may be increased simply by using a
larger
cross-section conductor of "non-fractal" construction.


The whole video sounded like a lot of verbal sleight of hand to me.
Its a shame techs and engineers are not secure enough in their
knowledge to recongnize BS when they hear it and report it as such.
"The Emperor's New Antenna".

Jimmie

Jimmie


Hello Jimmie,

It may not be magic (cheating), but it does not mean that this is the
only solution to get a wide band antenna with reasonable radiation
pattern.

Adding a second (even non-radiating) resonator to a quarter wave whip
(or similar structure) does increase the useful bandwidth with a
factor 2.5. I used this technique in some commercial UHF designs.
"Electrically Small, Superdirective, and Superconducting Antennas" ,
R.C. Hansen, discusses the resonator technique also.

Adding a third resonator will give slightly more increase of useful
bandwidth. Basically it uses the same design techniques as used in
broad-banding amplifiers with LC sections. Looking to VSWR versus
frequency, it looks like the put the resonator technique in a fractal
appearance.

In very wide band applications ( 3:1), you can keep the VSWR within
reasonable limits, but a whip-type radiating element may result in a
clover radiation pattern. Flared thick structures give better
radiation pattern.

Best regards,


Wim
PA3DJS
www.tetech.nl
without abc, PM will reach me very likely.


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Old January 4th 11, 06:54 PM posted to rec.radio.amateur.antenna
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Posts: 2,951
Default Fractal Sleeve for Monopoles?

On Wed, 22 Dec 2010 05:13:39 -0800 (PST), Richard Fry
wrote:

Observations from watching the YouTube video...


The gain units used in the video are therefore unconventional, and
need further
definition.


Hi Richard,

Leave it at unconventional - that word's definition is well
understood.

3. The relative field radiated by a conventional 1/4-wave vertical
monopole
driven against a perfectly conducting ground plane always is maximum
in the
horizontal plane. Such a system radiates virtually 100% of the matched
power
applied to its input terminals.


This reveals a common flaw found in vertical antenna analysis when
compared to AM antenna measurement conventions. Simply put, if you
lift the antenna off of an infinite plane, you lose 3dB. It is
demonstrable with even the meagerest of antenna modelers.

Chip's antenna is in the air, not on an infinite plane. A solid disk
replacing a field of radials does NOT constitute a replacement for an
infinite plane such as to recover the 3dB. This might account for the
bookkeeping error in the vendor's favor.

I believe somewhere in the tightly scripted presentation it was
asserted that there was no "figure 8" pattern as one would expect of
an antenna in free space.

The antenna is "apparently" in an anechoic chamber - or free space as
closely as can be approximated. There are no reports of the far field
envelope shape.

So let's mark it up to Chip's usual technique of loose suggestion
being passed off as a citation to then be wrapped back as a proof.

Therefore the peak gain of that antenna system at resonance cannot be
improved
by putting a sleeve of any kind on the monopole.


I would dispute that. The evidence is sufficient insofar as the
indication of change in the before/after display on instrumentation.
Unless this is some form of parsing what "peak gain" means. What you
write immediately following already conforms to that instrument
display:

The sleeve may change the shape of the radiation pattern of the system
without
the sleeve, though, which could change the field intensity at the
location of
the receiving antenna used in the test. This could account for the ~3
dB
improvement shown in their results when using the sleeve.


And by what you say above, this is the entirety of it. A thicker
radiator - nothing less than has been covered in text for decades. You
observe that below.

4. Nothing is shown in the video about the amount of matched power at
the
feedpoint with and without the sleeve. If that is not held constant
then the
test will be flawed.


The instrumentation already takes care of that, and is discussed early
in the presentation. I was doing this kind of bench work, with this
kind of instrumentation, in this band, 20 years ago.

5. The VSWR bandwidth of a monopole may be increased simply by using a
larger
cross-section conductor of "non-fractal" construction.


Of course - but that information doesn't sell product.

73's
Richard Clark, KB7QHC
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Old January 4th 11, 07:57 PM posted to rec.radio.amateur.antenna
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Posts: 1,339
Default Fractal Sleeve for Monopoles?

On Jan 4, 11:54*am, Richard Clark wrote:
On Wed, 22 Dec 2010 05:13:39 -0800 (PST), Richard Fry
wrote:

Observations from watching the YouTube video...
The gain units used in the video are therefore unconventional, and
need further
definition.


Hi Richard,

Leave it at unconventional - that word's definition is well
understood.

3. The relative field radiated by a conventional 1/4-wave vertical
monopole
driven against a perfectly conducting ground plane always is maximum
in the
horizontal plane. Such a system radiates virtually 100% of the matched
power
applied to its input terminals.


This reveals a common flaw found in vertical antenna analysis when
compared to AM antenna measurement conventions. *Simply put, if you
lift the antenna off of an infinite plane, you lose 3dB. *It is
demonstrable with even the meagerest of antenna modelers.

Chip's antenna is in the air, not on an infinite plane. *A solid disk
replacing a field of radials does NOT constitute a replacement for an
infinite plane such as to recover the 3dB. *This might account for the
bookkeeping error in the vendor's favor.

I believe somewhere in the tightly scripted presentation it was
asserted that there was no "figure 8" pattern as one would expect of
an antenna in free space.

The antenna is "apparently" in an anechoic chamber - or free space as
closely as can be approximated. *There are no reports of the far field
envelope shape.

So let's mark it up to Chip's usual technique of loose suggestion
being passed off as a citation to then be wrapped back as a proof.

Therefore the peak gain of that antenna system at resonance cannot be
improved
by putting a sleeve of any kind on the monopole.


I would dispute that. *The evidence is sufficient insofar as the
indication of change in the before/after display on instrumentation.
Unless this is some form of parsing what "peak gain" means. *What you
write immediately following already conforms to that instrument
display:



The sleeve may change the shape of the radiation pattern of the system
without
the sleeve, though, which could change the field intensity at the
location of
the receiving antenna used in the test. This could account for the ~3
dB
improvement shown in their results when using the sleeve.


And by what you say above, this is the entirety of it. *A thicker
radiator - nothing less than has been covered in text for decades. You
observe that below.

4. Nothing is shown in the video about the amount of matched power at
the
feedpoint with and without the sleeve. If that is not held constant
then the
test will be flawed.


The instrumentation already takes care of that, and is discussed early
in the presentation. *I was doing this kind of bench work, with this
kind of instrumentation, in this band, 20 years ago.

5. The VSWR bandwidth of a monopole may be increased simply by using a
larger
cross-section conductor of "non-fractal" construction.


Of course - but that information doesn't sell product.

73's
Richard Clark, KB7QHC


He is using a resonator to drive another radiater
( see constant impedance antenna system patent) The radiator that he
is driving is of multiple wavelength as in a wire mesh where the
multiple routes that can be taken by current flow provides an ultra
wide frequency span as the reactance changes become smaller and
smaller.
The final radiator is a full wave or more closed circuit version which
provides more gain than a fractional length over a ground plane
Very simple use of a metamaterial which has been demonstrated in most
universities of the day.
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