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Old November 6th 09, 04:11 AM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna

Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?


Maybe the quadrifilar helix.

tom
K0TAR
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Old November 6th 09, 04:05 PM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna

On Nov 5, 10:11*pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?


Maybe the quadrifilar helix.

tom
K0TAR


That is made for a single circulation signal only.
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Old November 7th 09, 03:10 AM posted to rec.radio.amateur.antenna
tom tom is offline
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Default Multi polarization antenna

Art Unwin wrote:
On Nov 5, 10:11 pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?

Maybe the quadrifilar helix.

tom
K0TAR


That is made for a single circulation signal only.


Then it's a point driven against ground that you need. Or a 2 point
dipole. Either one with a lossless transmission line would work.

That's the only thing that will do all you want and do both RHC and LHC
polarizations and do it at all frequencies. I have to assume you want
all frequencies since you haven't responded on that question.

And it will have a very unusable impedance at all frequencies. But if
you can do the lossless line, you are probably covered on the lossless
tuner, too.

Good luck. You want everything, and you can't have it.

And "single circulation" is not the proper terminology (as usual),
although I am somewhat sure about what you meant.

tom
K0TAR
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Old November 7th 09, 03:28 PM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna

On Nov 6, 9:10*pm, tom wrote:
Art Unwin wrote:
On Nov 5, 10:11 pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?
Maybe the quadrifilar helix.


tom
K0TAR


That is made for a single circulation signal only.


Then it's a point driven against ground that you need. *Or a 2 point
dipole. *Either one with a lossless transmission line would work.

That's the only thing that will do all you want and do both RHC and LHC
polarizations and do it at all frequencies. *I have to assume you want
all frequencies since you haven't responded on that question.

And it will have a very unusable impedance at all frequencies. *But if
you can do the lossless line, you are probably covered on the lossless
tuner, too.

Good luck. *You want everything, and you can't have it.

And "single circulation" is not the proper terminology (as usual),
although I am somewhat sure about what you meant.

tom
K0TAR


I wanted to know if there was such a radiator in the system that could
do such a thing and apparently there is not! I am working on one that
will do it but I wanted to be sure if I was
not reinventing the wheel.
My antenna is based on using something like a ladder line only with
the wires closer together to provide a lower impedance. If you close
both ends of such a line and wind a helix with it you can get a
radiator beam that will do all the things I suggested except the "all
frequency" part which requires further additions .
If you have two open wires in parallel and slide a cross connector up
and down the two wires the resonant frequency changes dependent on the
length where the jumper is.
Thus, if you literally make the ladder line into a true ladder by
fixing a lot of conductive cross rungs on the ladder, the applied
current will cross over at the point that the circuit is resonant.
This way the radiator will get the "all frequency" attributes.
Such a radiator becomes a much physically smaller radiator than is
being used today.
Why not try it.?... It is the proverbial free lunch!
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Old November 7th 09, 04:48 PM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna


"Art Unwin" wrote in message
...
On Nov 6, 9:10 pm, tom wrote:
Art Unwin wrote:
On Nov 5, 10:11 pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?
Maybe the quadrifilar helix.


tom
K0TAR


That is made for a single circulation signal only.


Then it's a point driven against ground that you need. Or a 2 point
dipole. Either one with a lossless transmission line would work.

That's the only thing that will do all you want and do both RHC and LHC
polarizations and do it at all frequencies. I have to assume you want
all frequencies since you haven't responded on that question.

And it will have a very unusable impedance at all frequencies. But if
you can do the lossless line, you are probably covered on the lossless
tuner, too.

Good luck. You want everything, and you can't have it.

And "single circulation" is not the proper terminology (as usual),
although I am somewhat sure about what you meant.

tom
K0TAR


I wanted to know if there was such a radiator in the system that could
do such a thing and apparently there is not! I am working on one that
will do it but I wanted to be sure if I was
not reinventing the wheel.
My antenna is based on using something like a ladder line only with
the wires closer together to provide a lower impedance. If you close
both ends of such a line and wind a helix with it you can get a
radiator beam that will do all the things I suggested except the "all
frequency" part which requires further additions .
If you have two open wires in parallel and slide a cross connector up
and down the two wires the resonant frequency changes dependent on the
length where the jumper is.
Thus, if you literally make the ladder line into a true ladder by
fixing a lot of conductive cross rungs on the ladder, the applied
current will cross over at the point that the circuit is resonant.
This way the radiator will get the "all frequency" attributes.
Such a radiator becomes a much physically smaller radiator than is
being used today.
Why not try it.?... It is the proverbial free lunch!


Are you saying a wave on a transmission line will continue to propagate
beyond a short-circuit across the line? If so, you've missed something
important.

Chris




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Old November 7th 09, 05:56 PM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna

On Nov 7, 10:48*am, "christofire" wrote:
"Art Unwin" wrote in message

...
On Nov 6, 9:10 pm, tom wrote:



Art Unwin wrote:
On Nov 5, 10:11 pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t..c
at the tower top?
Maybe the quadrifilar helix.


tom
K0TAR


That is made for a single circulation signal only.


Then it's a point driven against ground that you need. Or a 2 point
dipole. Either one with a lossless transmission line would work.


That's the only thing that will do all you want and do both RHC and LHC
polarizations and do it at all frequencies. I have to assume you want
all frequencies since you haven't responded on that question.


And it will have a very unusable impedance at all frequencies. But if
you can do the lossless line, you are probably covered on the lossless
tuner, too.


Good luck. You want everything, and you can't have it.


And "single circulation" is not the proper terminology (as usual),
although I am somewhat sure about what you meant.


tom
K0TAR


I wanted to know if there was such a radiator in the system that could
do such a thing and apparently there is not! I am working on one that
will do it but I wanted to be sure if I was
not reinventing the wheel.
My antenna is based on using something like a ladder line only with
the wires closer together to provide a lower impedance. If you close
both ends of such a line and wind a helix with it you can get a
radiator beam that will do all the things I suggested except the "all
frequency" part which requires further additions .
If you have two open wires in parallel and slide a cross connector up
and down the two wires the resonant frequency changes dependent on the
length where the jumper is.
Thus, if you literally make the ladder line into a true ladder by
fixing a lot of conductive cross rungs on the ladder, the applied
current will cross over at the point that the circuit is resonant.
This way the radiator will get the "all frequency" attributes.
Such a radiator becomes a much physically smaller radiator than is
being used today.
Why not try it.?... It is the proverbial free lunch!

Are you saying a wave on a transmission line will continue to propagate
beyond a short-circuit across the line? *If so, you've missed something
important.

Chris


Not sure what you are getting at Chris.
The applied current will travel the 1/2 WL of the radiator/
transmission line and then turn so it will be at resonant impedance at
the input, at the impedance value of the line. The current will not
continue to travel any further than when the closed circuit that is
resonant is reached. In other words, a transmission line can be seen
as having the same impedance or load at each end at a given frequency.
If you close one end, is it not still resonant? If you want to dig
further look at my home page unwinantennas to see where I am coming
from.
This is the same principle used when matching a radiator with
transmission line sections as shown on a nearby current thread ( at
least that is the way I see it but then I could still be a fraud by
any other name!) I have done this many times in practice BUT it may
well be the "why's) that I am misinterpreting.
On the other hand I cannot see how a AC circuit wil short across as
you have intimated.
Again I could be wrong as usual! When I model such an arrangement it
provides gain in the order of 10dbi +/- 1.5 db regardless of the type
of radiation that is directed at it. Well one type doesn't work out
well but I don't know where it is usedn in today's world
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Old November 7th 09, 06:09 PM posted to rec.radio.amateur.antenna
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Default Multi polarization antenna

On Sat, 7 Nov 2009 16:48:55 -0000, "christofire"
wrote:

My antenna is based on using something like a ladder line only with
the wires closer together to provide a lower impedance.

....
Thus, if you literally make the ladder line into a true ladder by
fixing a lot of conductive cross rungs on the ladder, the applied
current will cross over at the point that the circuit is resonant.


Hi Chris,

So, you want to turn a massively shorted thin transmission line into a
radiator?

How does the current get past the first short? It cannot, so that
string of shorts up the line are redundant and you can remove them.
This leaves you with a very small loop very close to the transmitter.
Almost every ham has tried working into a short and has never found it
productive. Have you tried it?

73's
Richard Clark, KB7QHC
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Old November 8th 09, 12:49 AM posted to rec.radio.amateur.antenna
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Posts: 173
Default Multi polarization antenna


"Richard Clark" wrote in message
...
On Sat, 7 Nov 2009 16:48:55 -0000, "christofire"
wrote:

My antenna is based on using something like a ladder line only with
the wires closer together to provide a lower impedance.

...
Thus, if you literally make the ladder line into a true ladder by
fixing a lot of conductive cross rungs on the ladder, the applied
current will cross over at the point that the circuit is resonant.


Hi Chris,

So, you want to turn a massively shorted thin transmission line into a
radiator?

How does the current get past the first short? It cannot, so that
string of shorts up the line are redundant and you can remove them.
This leaves you with a very small loop very close to the transmitter.
Almost every ham has tried working into a short and has never found it
productive. Have you tried it?

73's
Richard Clark, KB7QHC



Shouldn't you be addressing Art Unwin with that? ... it's he who's proposing
the idea, not me.

Perhaps the behaviour of Outlook Express has led to confusion (again?),
despite my leaving a double line space between the OP and my comment.

Chris


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Old November 7th 09, 06:32 PM posted to rec.radio.amateur.antenna
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Posts: 1,336
Default Multi polarization antenna

On Fri, 6 Nov 2009 08:05:17 -0800 (PST), Art Unwin
wrote:

On Nov 5, 10:11*pm, tom wrote:
Art Unwin wrote:
What is the best antenna for use with all circular, horizontal,
vertical and other polarizations without drastic fall of in gain, and
without changes in angular position and feed point via switches e.t.c
at the tower top?


Maybe the quadrifilar helix.

tom
K0TAR


That is made for a single circulation signal only.


It might be done with 4 quadrifilar antennas. Each antenna has a
hemispherical pattern and one sense (left or right hand). With 4
antennas and a suitable combiner, each antenna will cover one half of
the pattern, and one of the two available senses. The quadrifilar
antenna will work with linear polarization, but at reduced gain. The
usable bandwidth is probably insufficient to cover DC to light, but
multiple quadrifilar antennas can be attached to the surface of a
ball, resulting in a sperical pattern approximation and a construction
that looks like a puffer fish. It's also possible to conglomerate the
quadrifiler into a tapered helix, thus increasing the bandwidth at the
expense of gain. For VLF, shove a ferrite rod into the middle.

You can also do random polarizations by using leaky coax, tangled into
a Gordian Knot. Some part of the knot will undoubtably be parallel to
the random polarization, and thus provide some signal pickup. Gain
will be limited by the length of the lossy coax and size of the knot.
http://www.afltele.com/products/fiber_optic_cable/coax_cable/leaky_coax/
http://en.wikipedia.org/wiki/Gordian_knot

Marginally related drivel:
http://www.wifi-plus.com
http://www.connectronics.com/wifi_plus/
"The world's first MULTI-POLARIZED - MULTI-PATH Antenna with
GEO-Spatial capture".


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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