I am looking for the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

On 19 Oct, 18:31, "Stefan Wolfe" wrote:
"John Doe" wrote in message

...

I am looking for the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

John, there is no such thing as a fractal antenna. Antennas can only
function in real space-time. It is a only figment of certain matematicians'
imaginations. Sorry. 73

Sorry.
There is a patent issued and many, many, more in the pipeline.
Look up Fractus antennas or subscribe to the quarterly industrial
magazine
called Antennas.The Fractus company was featured at the Antenna
exhibition in
Denver last month. Entrance fee was about $1000
At the companies inception it won seed money from the military
to continue their work so the antenna is viable.

Oh no Here we go again.

10 years ago this was a major topic

and ridicule

On Oct 19, 11:11 pm, "R. Scott"
wrote:
Oh no Here we go again.

10 years ago this was a major topic

and ridicule

Yea, if there is a new company called "Fractus", I bet a
character called Chippus is about to have kittens.
Maybe six or seven of them.
With little curly tails...
Fractus... Kinda reminds me of Festus...
Maaaathheeeewwww! What thar heck is that curly waaar
you got stuck on that there horses head?
Doc, have you ever done seen such a thang?
Miss Kitty! Maaaatheewws horse has a bed sprang
on his head! I done declare!

"John Doe" wrote in message
...
I am looking for the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

As others have mentioned, several articles appeared in various magazines
about the design of fractal antennas. The basic idea is to fold a standard
length of wire using a fractal pattern so that it fits into a smaller space.
One solution I saw was to wind a wire back and forth across and along a
plank of wood using pins or slots cut in the wood to support the turns.
Taking a four inch wide piece of wood around eight feet long and winding
equispaced turns you could easily fit 24 feet of wire along the plank.
__ __ __
|__| |__| |__| | Using a pattern like this.

Other more complex or even three dimensional designs can fit more wire into
a given space.

Older interpretations of antenna theory predicted that the interaction
between the closely spaced wires would effectively short out the turns and
you would end up with the equivalent of an 8 foot length radiating element
rather than the 24 feet of wire wound along the plank of wood. While there
is interaction, the apparent reduction in radiator element length is not as
bad as was predicted. So fractally wound elements can be worth the effort
where space is at a premium.

It is significant that the majority of development work into these antennas
has taken place for frequencies above 1Ghz. Main applications include mobile
phones, RF ID tags, security and remote sensing tags. At Ghz frequencies,
exotic patterns can be easily etched onto circuit boards at minimal cost.
Koch snowflake like fractal patterns combined with circular whorls seem very
popular with commercial manufacturers. A google search will reveal quite a
few pictures of what is being produced.

It is not necessary to try and duplicate the complexity of professional
designs. The main criteria seems to be to keep the wires as evenly spaced as
possible, hence the width of the winding should be approximately equal to
the linear step along the plank of wood or whatever support frame you are
using, i.e. 4 inches up, 4 inches along, 4 inches down, four inches along, 4
inches up, etc. etc.

As you will doubtless appreciate, this is similar to a three dimensional
coil being wound on a former. Because the fractal winding is flat, there are
fewer inductance effects.

Obviously fractal antennae are designed for a specific frequency or band,
but the type of winding pattern and spacing have an effect on the bandwidth.
Obviously you will need two mirror image windings to create a dipole
antenna, ideally as closely matched in dimensions as possible. Efficiencies
can approach 50% of a full sized radiating element.

Hope this helps

Mike G0ULI

On Oct 20, 12:19 pm, wrote:



Oh no Here we go again.

10 years ago this was a major topic

and ridicule


From the many Luddites on this group.

Derek.

wrote:
On Oct 19, 11:11 pm, "R. Scott"
wrote:
Oh no Here we go again.

10 years ago this was a major topic

and ridicule

Yea, if there is a new company called "Fractus", I bet a
character called Chippus is about to have kittens.
Maybe six or seven of them.
With little curly tails...
Fractus... Kinda reminds me of Festus...
Maaaathheeeewwww! What thar heck is that curly waaar
you got stuck on that there horses head?
Doc, have you ever done seen such a thang?
Miss Kitty! Maaaatheewws horse has a bed sprang
on his head! I done declare!


Please dont call on the Unnamed Chippus you may revive
him from the evil dead so he can threaten not to sell
his products to your company

On 20 Oct, 04:59, "Mike Kaliski" wrote:
"John Doe" wrote in message

...I am looking for the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

As others have mentioned, several articles appeared in various magazines
snip.
Obviously you will need two mirror image windings to create a dipole
antenna,

Mike,
the definition I arrived at is that as long as the wire represents one
wave length,
is resonant and in equilibrium while at the same time holding to the L/
C ratio of the material in question.
This can be produced with just two degrees of freedom by folding
the wire at the half wave point
and then wind the two wires in pancake shape/form.
You can also wind two in series where capacitive actions
between them can create a variety of results.
The important point is that one must hold to the
conditions set in the definition
(no exceptions)

Art





ideally as closely matched in dimensions as possible. Efficiencies
can approach 50% of a full sized radiating element.

Hope this helps

Mike G0ULI

"art" wrote in message
oups.com...
On 20 Oct, 04:59, "Mike Kaliski" wrote:
"John Doe" wrote in message

...I am looking for
the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

As others have mentioned, several articles appeared in various magazines
snip.
Obviously you will need two mirror image windings to create a dipole
antenna,

Mike,
the definition I arrived at is that as long as the wire represents one
wave length, is resonant and in equilibrium while at the same time holding
to the L/C ratio of the material in question. This can be produced with
just two degrees of freedom by folding the wire at the half wave point and
then wind the two wires in pancake shape/form.
You can also wind two in series where capacitive actions between them can
create a variety of results.
The important point is that one must hold to the conditions set in the
definition (no exceptions)

Art

ideally as closely matched in dimensions as possible. Efficiencies
can approach 50% of a full sized radiating element.

Hope this helps

Mike G0ULI


Art

I agree. Incidently the origin of the idea for fractal antennae apparently
arose from the observation that hanging down the ends of a dipole, or
bending it to fit a limited site didn't affect the efficiency too much. A
university student decided to see just how much bending and could take place
before the antenna became unusable and hey presto, the fractal antenna was
invented and he had a thesis for his degree.

Mike G0ULI

On 20 Oct, 09:34, "Mike Kaliski" wrote:
"art" wrote in message

oups.com...



On 20 Oct, 04:59, "Mike Kaliski" wrote:
"John Doe" wrote in message

om...Iam looking for
the construction article "FRACTAL Antenna for 10m" that
appeared sometime ago in I think either QST, Ham Radio, or 73 magazines.

I have a lot of spare time on my hands - so I thought I would like to
construct one and use it portable as I live in a Antenna Restricted
Community.

73's

As others have mentioned, several articles appeared in various magazines
snip.
Obviously you will need two mirror image windings to create a dipole
antenna,

Mike,
the definition I arrived at is that as long as the wire represents one
wave length, is resonant and in equilibrium while at the same time holding
to the L/C ratio of the material in question. This can be produced with
just two degrees of freedom by folding the wire at the half wave point and
then wind the two wires in pancake shape/form.
You can also wind two in series where capacitive actions between them can
create a variety of results.
The important point is that one must hold to the conditions set in the
definition (no exceptions)

Art

ideally as closely matched in dimensions as possible. Efficiencies
can approach 50% of a full sized radiating element.

Hope this helps

Mike G0ULI

Art

I agree. Incidently the origin of the idea for fractal antennae apparently
arose from the observation that hanging down the ends of a dipole, or
bending it to fit a limited site didn't affect the efficiency too much. A
university student decided to see just how much bending and could take place
before the antenna became unusable and hey presto, the fractal antenna was
invented and he had a thesis for his degree.

Mike G0ULI- Hide quoted text -

- Show quoted text -

Yup He is way ahead of the average ham but he did have an engineering
background
now he is making a lot of money with a product that the average hame
decries.
I was looking at Tom's page W8ti and I was very suprised to see that
he states
an antenna must be straight no less plus a lot more in accurate
statements.
He has written articles as have many on this newsgroup but as I have
stated before
believe what you want but often it is not correct.
On this newsgroup I am often reminded of the scene around madame
guillotine with
the . hoards of baying crowds of the ignorant looking for blood.
Have to make a correction on past statements tho, instead of one
wavelength radiator it should read
" one wavelength or longer" because of the genorous number of
harmonics.
Cheers
Art KB9MZ....XG (uk)