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Dave April 4th 08 12:02 PM

Antenna physical size
 

wrote in message
...
On Apr 2, 11:12 pm, Art Unwin wrote:
On Apr 2, 10:37 pm, wrote:

On Apr 2, 1:41 pm, Art Unwin wrote:


Pray tell me then why I am incorrect. You can salvage the
answer from your own mind or even from a book.
When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium.


Define equilibrium as it pertains to an antenna. Until you do, it's
fairly hard to comment on the first statement.


I don't think I can do that for you, it would take to long.


It hasn't stopped you from writing a novel on other issues..

If you have corona discharge from an antenna, it's usually due
to sharp points when using wire or a whip with a pointed tip.
Thats why they stick round balls on whips, flagpoles, etc..


When you have a discharge it is a loss of energy


Not antenna efficiency though. It's more akin to running a
dipole with poor end insulators..

When a dipole is replaced by a quad ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter is more efficient.


What clearly shows this?


Well there is no discharge. This is becaquse that there is a route
of a lesser impedance available


Has nothing to do with antenna efficiency.

This is the statement which drew my comment.
The efficiency of a 1/2 WL dipole and a 1 WL loop are so close as
to be almost unmeasurable in the real world.


Almost doesn't count when measuring efficiency and in the real world
many CAN tell the difference But you can take this even farther. Almost
*any* size dipole
or loop will radiate most all of what is fed to it.


Again you are admitting to lower efficiency when you use the word
"most"


The only reason I use "most" is because no real world antenna will
radiate 100% of the power applied to it.


A 1/10 WL whip radiates almost all of the power applied to
it, same as a 1/4 WL, 1/2 WL, or whatever you want to try.
This not not conjecture. This is pretty much written in stone
after many years of testing.


Again you use the word "most" which is admitting less efficiency


No, it's admitting that no real antenna will radiate 100% of the
power fed to it. Has nothing to do with a comparison of the
various types.

Why you continue to ignore this simple fact boggles my mind.
So your statement is so far from reality I would be amiss
in my "talking head" duties if I did not comment.
Don't take my word for it. Ask anyone you can think of
that has a clue. They will tell you the same thing.


What it going to spoil your "full size performance from a
dinky radiator" picnic is not the radiator and it's abilities to be
an efficient radiator.
It's going to be actually feeding the power to such a small
radiator and not turning a large amount of RF to heat in the
process. No cheating letting the feed line be the antenna..


I think you are missing the point here. My antenna has a full wave
length of wire
not a fraction there of.


So? From it's claimed performance, it's working as a
great dummy load.
You say it requires no matching to coax, and
covers the whole 160m band..
This simple description tells me your antenna is a
poor radiator of RF. It shows all the qualities of a
air cooled dummy load.
A truly efficient antenna of such a small size would
require matching to the feedline, would be quite high Q,
and the bandwidth would be very narrow.
So narrow as to possibly restrict the audio quality
of the average 2.5- 3 kc transmitter width .. :(
You can actually hear the restriction on the air.
I've noticed this many times when people try
very small high Q antennas on that band..
This is reciprical, and will be noticed on receive
also if you A/B between a full size antenna vs
the small version.

So the radiator has the same inductance and
capacitance
that one would expect from a full wave antenna spread out in a
straight line


You wish...

where the wire surface is exposed to the atmosphere, so there is no
reason
for the energy to circumvent the wire circuit as it must do for a
fractional wavelength.


Oh, like it does with a 1/2 wave dipole... :/


Look at "small" HF transmitting loops. Do you see any
using 22 gauge wire? I doubt it.
They will be using the fattest or widest strip of material
they can get their hands on.


What you are seeing as representing a loop antenna is a fractional
wave length
Often it comes with a HV variable capacitor for tuning.

The loop that I made was a plastic loop with a full wave length of
wire wound upon it. No high voltage capacitor needed as it coveres
the whole band.


Didn't work very well as a radiator of RF did it...
Good dummy load though I bet...

As far as 22 gauge wire being used this is because there is no
mechanical stresses
imposed on it as would be for a stretched out radiator. So the main
consideration
is to supply enough skin depth since the diameter itself
is not a factor in terms of fusing.current


I didn't know you were trying to construct a fuse box...

There are other issues involved also in feeding such an
antenna. Never do these small loops equal the performance
of a full size antenna. They radiate enough to maybe let
you operate, and thats about it.


If the scource impedance is one that you can match efficiently
then you have at hand a efficient radiator


Like a dummy load?

of a wavelength where
the normal loop you are refering to uses a metal loop as the radiator
which is much shorter than a wavelength of wire wound on a plastic
loop.
The loop is now a small full wave radiator not a small fractional
small wave antenna


No, it's a small antenna, coil loaded with many feet of 22 gauge
wire. In fact, the antenna is pretty much all coil.
Not too much different than a wound loopstick used for MW.
Their virtues as efficient radiators of RF are about nil.. :(



This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period


Again, the change to quad loops at HCJB was to
avoid the sharp points of the dipoles, yagi's, or
whatever they were using. In the high alitudes of
Quito, HV breakdown at the tips was a serious problem.
The change had absolutely nothing to do with antenna
efficiency.


If the impedance is to high on the antenna compared to
discharging through air to the transmitter ground then that
is a very inefficient antenna


No. It has nothing to do with antenna efficiency.
Antenna efficiency is reciprical from receive to
transmit.
It's like me taking a nearly fully efficient dipole
and running it through a bunch of wet tree branches
with poor insulators, and then running high power.
An antenna that is truly inefficient will be inefficient
on both transmit and receive.
Obviously in the case of the dipole, this is not the
case. When receiving only, I bet it works just fine.


Not to mention that the whole idea of a loop being
more efficient than a dipole is totally wrong.


The energy travels easily along the wire circuit without
encountering a high impedance that it is forced to take a circuitous
route thru ground to the transmitter ground. When the energy
is passing thru ground it becomes a loss.


Where does ground enter the picture?

And I don't see how equilibrium has anything to
do with it, whatever you might mean by that silly "E"
word.


If a circuit is not balanced and a fractional wave length long
it is not in equilibrium!.


But you won't define the E word, so this means little to
me...


The energy supplied to the radiator
will always encounter a energy wasting impedance in the wire itself if
is not at least a wavelength long, and of the right material
(diamagnetic)


Wire resistance does not go away if you use larger lengths of
wire vs shorter when using an equal wire gauge.

otherwise the energy will seek a route outside the wired circuit which
can only lead to losses. Think of it this way, a fractional wave
length radiator
cannot avoid the energy taking a route thru ground and the ground is a
loss.


What about the 1/2 wave dipole?

Hopefully you now see antennas in a different light.


Nope.. Why would I?

I do urge you to
look up
the tank circuit since it is quite an interesting circuit with its
phase changes
and effective resistances apparently changing without being diverted
from the circuit wire confines.


I've already read about tank circuits..

Another place where the books are in
error
is their association with the iron filing magnet experiment at HS
which
forms a magnetic field very different from that formed from aluminum,
copper and other diamagnetic materials. When you pass a time varying
current thru
copper the magnetic field turns at right angles to the radiator axis
and in fact
compliments the electrical field vector ( they are not at right
angles)
Now you can see what lifts or ejects the static particles resting on
the surface
because they are repelled instead of bing magnetically atracted
( Static: nearly devoid of energy and of small mass)


RF is never static..

. So the EH antennas which supposedly combines the EH fields just
didn't
understand that with a radiator the combination of vectors is already
a given!


Which means what?

I think you also are making a mistake that many books make when
referring to
small antennas instead of referring to ELECTRICALLY small antennas


You are thinking wrong.



you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.



[email protected] April 4th 08 01:50 PM

Antenna physical size
 
On Apr 4, 7:02 pm, "Dave" wrote:
wrote in message

... On Apr 2, 11:12 pm, Art Unwin wrote:
On Apr 2, 10:37 pm, wrote:


On Apr 2, 1:41 pm, Art Unwin wrote:


Pray tell me then why I am incorrect. You can salvage the
answer from your own mind or even from a book.
When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium.


Define equilibrium as it pertains to an antenna. Until you do, it's
fairly hard to comment on the first statement.


I don't think I can do that for you, it would take to long.


It hasn't stopped you from writing a novel on other issues..


If you have corona discharge from an antenna, it's usually due
to sharp points when using wire or a whip with a pointed tip.
Thats why they stick round balls on whips, flagpoles, etc..


When you have a discharge it is a loss of energy


Not antenna efficiency though. It's more akin to running a
dipole with poor end insulators..


When a dipole is replaced by a quad ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter is more efficient.


What clearly shows this?


Well there is no discharge. This is becaquse that there is a route
of a lesser impedance available


Has nothing to do with antenna efficiency.


This is the statement which drew my comment.
The efficiency of a 1/2 WL dipole and a 1 WL loop are so close as
to be almost unmeasurable in the real world.


Almost doesn't count when measuring efficiency and in the real world
many CAN tell the difference But you can take this even farther. Almost
*any* size dipole
or loop will radiate most all of what is fed to it.


Again you are admitting to lower efficiency when you use the word
"most"


The only reason I use "most" is because no real world antenna will
radiate 100% of the power applied to it.


A 1/10 WL whip radiates almost all of the power applied to
it, same as a 1/4 WL, 1/2 WL, or whatever you want to try.
This not not conjecture. This is pretty much written in stone
after many years of testing.


Again you use the word "most" which is admitting less efficiency


No, it's admitting that no real antenna will radiate 100% of the
power fed to it. Has nothing to do with a comparison of the
various types.


Why you continue to ignore this simple fact boggles my mind.
So your statement is so far from reality I would be amiss
in my "talking head" duties if I did not comment.
Don't take my word for it. Ask anyone you can think of
that has a clue. They will tell you the same thing.


What it going to spoil your "full size performance from a
dinky radiator" picnic is not the radiator and it's abilities to be
an efficient radiator.
It's going to be actually feeding the power to such a small
radiator and not turning a large amount of RF to heat in the
process. No cheating letting the feed line be the antenna..


I think you are missing the point here. My antenna has a full wave
length of wire
not a fraction there of.


So? From it's claimed performance, it's working as a
great dummy load.
You say it requires no matching to coax, and
covers the whole 160m band..
This simple description tells me your antenna is a
poor radiator of RF. It shows all the qualities of a
air cooled dummy load.
A truly efficient antenna of such a small size would
require matching to the feedline, would be quite high Q,
and the bandwidth would be very narrow.
So narrow as to possibly restrict the audio quality
of the average 2.5- 3 kc transmitter width .. :(
You can actually hear the restriction on the air.
I've noticed this many times when people try
very small high Q antennas on that band..
This is reciprical, and will be noticed on receive
also if you A/B between a full size antenna vs
the small version.


So the radiator has the same inductance and
capacitance
that one would expect from a full wave antenna spread out in a
straight line


You wish...


where the wire surface is exposed to the atmosphere, so there is no
reason
for the energy to circumvent the wire circuit as it must do for a
fractional wavelength.


Oh, like it does with a 1/2 wave dipole... :/


Look at "small" HF transmitting loops. Do you see any
using 22 gauge wire? I doubt it.
They will be using the fattest or widest strip of material
they can get their hands on.


What you are seeing as representing a loop antenna is a fractional
wave length
Often it comes with a HV variable capacitor for tuning.


The loop that I made was a plastic loop with a full wave length of
wire wound upon it. No high voltage capacitor needed as it coveres
the whole band.


Didn't work very well as a radiator of RF did it...
Good dummy load though I bet...


As far as 22 gauge wire being used this is because there is no
mechanical stresses
imposed on it as would be for a stretched out radiator. So the main
consideration
is to supply enough skin depth since the diameter itself
is not a factor in terms of fusing.current


I didn't know you were trying to construct a fuse box...


There are other issues involved also in feeding such an
antenna. Never do these small loops equal the performance
of a full size antenna. They radiate enough to maybe let
you operate, and thats about it.


If the scource impedance is one that you can match efficiently
then you have at hand a efficient radiator


Like a dummy load?


of a wavelength where
the normal loop you are refering to uses a metal loop as the radiator
which is much shorter than a wavelength of wire wound on a plastic
loop.
The loop is now a small full wave radiator not a small fractional
small wave antenna


No, it's a small antenna, coil loaded with many feet of 22 gauge
wire. In fact, the antenna is pretty much all coil.
Not too much different than a wound loopstick used for MW.
Their virtues as efficient radiators of RF are about nil.. :(


This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period


Again, the change to quad loops at HCJB was to
avoid the sharp points of the dipoles, yagi's, or
whatever they were using. In the high alitudes of
Quito, HV breakdown at the tips was a serious problem.
The change had absolutely nothing to do with antenna
efficiency.


If the impedance is to high on the antenna compared to
discharging through air to the transmitter ground then that
is a very inefficient antenna


No. It has nothing to do with antenna efficiency.
Antenna efficiency is reciprical from receive to
transmit.
It's like me taking a nearly fully efficient dipole
and running it through a bunch of wet tree branches
with poor insulators, and then running high power.
An antenna that is truly inefficient will be inefficient
on both transmit and receive.
Obviously in the case of the dipole, this is not the
case. When receiving only, I bet it works just fine.


Not to mention that the whole idea of a loop being
more efficient than a dipole is totally wrong.


The energy travels easily along the wire circuit without
encountering a high impedance that it is forced to take a circuitous
route thru ground to the transmitter ground. When the energy
is passing thru ground it becomes a loss.


Where does ground enter the picture?


And I don't see how equilibrium has anything to
do with it, whatever you might mean by that silly "E"
word.


If a circuit is not balanced and a fractional wave length long
it is not in equilibrium!.


But you won't define the E word, so this means little to
me...


The energy supplied to the radiator
will always encounter a energy wasting impedance in the wire itself if
is not at least a wavelength long, and of the right material
(diamagnetic)


Wire resistance does not go away if you use larger lengths of
wire vs shorter when using an equal wire gauge.


otherwise the energy will seek a route outside the wired circuit which
can only lead to losses. Think of it this way, a fractional wave
length radiator
cannot avoid the energy taking a route thru ground and the ground is a
loss.


What about the 1/2 wave dipole?


Hopefully you now see antennas in a different light.


Nope.. Why would I?


I do urge you to
look up
the tank circuit since it is quite an interesting circuit with its
phase changes
and effective resistances apparently changing without being diverted
from the circuit wire confines.


I've already read about tank circuits..


Another place where the books are in
error
is their association with the iron filing magnet experiment at HS
which
forms a magnetic field very different from that formed from aluminum,
copper and other diamagnetic materials. When you pass a time varying
current thru
copper the magnetic field turns at right angles to the radiator axis
and in fact
compliments the electrical field vector ( they are not at right
angles)
Now you can see what lifts or ejects the static particles resting on
the surface
because they are repelled instead of bing magnetically atracted
( Static: nearly devoid of energy and of small mass)


RF is never static..


. So the EH antennas which supposedly combines the EH fields just
didn't
understand that with a radiator the combination of vectors is already
a given!


Which means what?


I think you also are making a mistake that many books make when
referring to
small antennas instead of referring to ELECTRICALLY small antennas


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.



[email protected] April 4th 08 02:08 PM

Antenna physical size
 

On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.



Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.

Derek

Dave April 4th 08 02:48 PM

Antenna physical size
 

wrote in message
...

On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either
case you
are fighting a losing battle.



Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.

Derek


please do enlighten us, art has failed miserably in that. i would love to
find out his antenna works as good as a full size half wave dipole and only
had to be tilted and turned on a tiny rotor... sure would be easier to
maintain than my current aluminum farm.



Art Unwin April 4th 08 04:22 PM

Antenna physical size
 
On Apr 4, 8:08 am, wrote:
On Apr 4, 7:02 pm, "Dave" wrote:
You are thinking wrong.


you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.

Derek


I thought I would share with you my readings on the 160 M band
They are in order as follows Freq, resistance, reactance swr

1.8 105 0 2.1
1.81 105 0 2.0
1.82 105 0 2.0
1.83 105 0 2.0
1.84 102 0 2.0
1.85 98 0 1.9
1.86 92 0 1.8
1.87 88 6 1.7
1.88 83 7 1.7
1.89 84 8 1.7
1.9 81 12 1.6
1.91 78 13 1.6
1.92 75 12 1.5
1.93 72 13 1.5
1.94 68 11 1.4
1.95 67 10 1.4
1.96 66 10 1.3
1.97 64 9 1.3
1.98 62 9 1.3
1.99 62 9 1.3
2.0 62 7 1.2
The above figures are obtained by ensuring no external inductance and
capacitances
were introduced to the intrinsic radiation circuit during assembly.
As one would expect, the above figures would represent the features
through out the frequency range
Impedance values mainly resistance will change according to the point
of jumper connection of wire supplied.
This allows for lossless matching to the drive circuit regardles of
its impedance value.
Those you are familiar with antennas will see that the above figures
in no way
represent those of a dummy load
'The above figures show an excellent match to 75 ohm cable. Thge
figures were taken with a
mfj 259b which is designed for 50 ohm cables.
TGIF
Art Unwin

Jim Lux April 4th 08 05:22 PM

Antenna physical size
 
wrote:
On Mar 31, 8:52 pm, Jim Lux wrote:

wrote:


Uhhh. actually there ARE laws of physics putting some pretty severe
constraints on it, if not actually forbidding it, if you also accept the
constraint that the material of which you make the antenna has finite
resistance.


Where ease might be defined in terms of being able to be made of
actually realizable materials?



The term 'actually realizable materials' seems to shift it's
definition every time something new is discovered :)



Sure, but there are "laws of physics" which determine the limits, at
some level. No materials with negative conductivity, for instance.

And, by "realizable" here, I mean practical, and a bit beyond. If one's
new and novel widget requires a 30 Tesla magnetic field, that's within
the laws of physics, but somewhat challenging to produce in a practical
sense.


Also, even if you created a very small antenna with high efficiency
(e.g. with superconductors), the fields around such an antenna will be
quite intense, so while the antenna may be small, its near field will be
pretty much the same size as the dipole it replaces, so you'll need to
put that tiny antenna way up in the air with a non-conductive, non-lossy
support to get it away from everything else. Finding a feedline might be
a bit of a challenge. One has to be careful when one draws "the
boundary" of the antenna.



Ok, it was my mistake to not clarify 'high efficiency'. By that I
meant 'at the same order of efficiency as normal scale designs'.
I am currenty interested by what I have seen claimed as 'compacted
antennas', which behave similar to normal ones, except their
dimensions are smaller, X-axis wise at least. That those designs do
not perform as well or better than their counterparts is no problem
to me, as long as the figures are in the same ballpark. That would
mean they still are more efficient than previous designs which
attempted to solve the problem of physical dimensions, which is an
advancement in my book. That some other unexpected features as the
broadband factor may appear is only a bonus, because we can achieve
that with full scale antennas too.


Where you're basically defining "efficiency" as power radiated into the
far field in a desired direction vs power into the feedline. That's a
fair definition for most amateur applications, if not necessarily
defensible in a rigorous analysis. Certainly, if you had two 40m band
antennas that were 3 meters across, and one produced a far field that
was twice that produced by the other, with the same transmitter power,
you'd be justified in saying the first antenna was more efficient than
the second, even if neither were particularly efficient in an absolute
sense (i.e. 2% vs 1% is a big jump in practical terms).



To be more specific, I was reffering to such designs that reduce the
scale of antennas in at least one axis:
http://adsabs.harvard.edu/abs/2004ITAP...52.1945P

This is an interesting paper.. I note that they use MoM to evaluate the
performance. It's a special case of a general class of antennas where
you have lots of little pieces that can be reconfigured by frequency
selective traps or rf switches to achieve wide feedpoint match bandwidth
in a small package. To a certain extent, the SteppIR is also in this
same class. The thing where you hook multiple hamstick loaded elements
onto one base is also similar. This paper addresses a moderately
systematic way to generate candidate physical layouts. Others have done
things like rectangular or hexagonal grids of wires or metallic patches.


http://ctd.grc.nasa.gov/organization...i-antennas.htm


A clever use of antenna layout to get multiband performance in a small
package. The small comes from fairly traditional approaches(i.e.
dielectric medium, bent and folded elements). I note that they don't
claim that it's comparable in efficiency to a full size antenna for the
same bands.

http://ntrs.nasa.gov/details.jsp?R=362773


That one is titled: "Ten Commandments Revisited A Ten-Year Perspective
on the Industrial Application of Formal Methods"

http://ntrs.nasa.gov/details.jsp?R=470415


That one is the executive summary of a Optical Systems technology
workshop held in 1991.


I have seen some of them described as fractal trees, but the
information is relatively scarce. I know research is continuing on
this subject and even found some info at a website somewhere but I
can't remember where. Since you probably know more about them than me,
I would appreciate some guidance here too :)


The antenna literature of the last 10 years is FULL of various and
sundry schemes for bending wires and brushes in one way or another
(mostly enabled by cheap computation to see how well it will work,
before fabricating a prototype). Check the IEEE Transactions on
Antennas and Propagation.

Michael Coslo April 4th 08 09:24 PM

Antenna physical size
 
wrote:
On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.
you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.



Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.



And always will be, just like modern washday miracles and Dishwashers
that don't leave spots on glasses. ;^)

An open mind does not mean suspension of all disbelief....


- 73 de Mike N3LI -

Art Unwin April 4th 08 09:56 PM

Antenna physical size
 
On Apr 4, 3:24 pm, Michael Coslo wrote:
wrote:
On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.
you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


And always will be, just like modern washday miracles and Dishwashers
that don't leave spots on glasses. ;^)

An open mind does not mean suspension of all disbelief....

- 73 de Mike N3LI -


Mike, you asked for a lot of details about the antenna such
that I thought you were going to make one. What happened
I expected you to come forward with confirmation in a lot of areas!
I thought you were a doer not a talking head.
Art

[email protected] April 4th 08 10:01 PM

Antenna physical size
 
On Apr 4, 9:22 am, Art Unwin wrote:


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


I already own a flashlight. Several in fact.




I thought I would share with you my readings on the 160 M band
They are in order as follows Freq, resistance, reactance swr

1.8 105 0 2.1
1.81 105 0 2.0
1.82 105 0 2.0
1.83 105 0 2.0
1.84 102 0 2.0
1.85 98 0 1.9
1.86 92 0 1.8
1.87 88 6 1.7
1.88 83 7 1.7
1.89 84 8 1.7
1.9 81 12 1.6
1.91 78 13 1.6
1.92 75 12 1.5
1.93 72 13 1.5
1.94 68 11 1.4
1.95 67 10 1.4
1.96 66 10 1.3
1.97 64 9 1.3
1.98 62 9 1.3
1.99 62 9 1.3
2.0 62 7 1.2

Those you are familiar with antennas will see that the above figures
in no way
represent those of a dummy load


I've seen light bulbs act the same way
when rf was fed to them.
How many people do you know that use a light
bulb as an antenna?
I used one as a dummy load when I was a novice.
It was enlightening, I have to admit that... :/



Art Unwin April 4th 08 11:15 PM

Antenna physical size
 
On Apr 4, 4:01 pm, wrote:
On Apr 4, 9:22 am, Art Unwin wrote:



Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


I already own a flashlight. Several in fact.





I thought I would share with you my readings on the 160 M band
They are in order as follows Freq, resistance, reactance swr


1.8 105 0 2.1
1.81 105 0 2.0
1.82 105 0 2.0
1.83 105 0 2.0
1.84 102 0 2.0
1.85 98 0 1.9
1.86 92 0 1.8
1.87 88 6 1.7
1.88 83 7 1.7
1.89 84 8 1.7
1.9 81 12 1.6
1.91 78 13 1.6
1.92 75 12 1.5
1.93 72 13 1.5
1.94 68 11 1.4
1.95 67 10 1.4
1.96 66 10 1.3
1.97 64 9 1.3
1.98 62 9 1.3
1.99 62 9 1.3
2.0 62 7 1.2


Those you are familiar with antennas will see that the above figures
in no way
represent those of a dummy load


I've seen light bulbs act the same way
when rf was fed to them.
How many people do you know that use a light
bulb as an antenna?
I used one as a dummy load when I was a novice.
It was enlightening, I have to admit that... :/


While listening to Europe coming in with 5/9 signasl,
I thought that everybody should be using "dummy loads"
Art

Dave April 4th 08 11:51 PM

Antenna physical size
 

"Art Unwin" wrote in message
...
On Apr 4, 4:01 pm, wrote:
On Apr 4, 9:22 am, Art Unwin wrote:



Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


I already own a flashlight. Several in fact.





I thought I would share with you my readings on the 160 M band
They are in order as follows Freq, resistance, reactance swr


1.8 105 0 2.1
1.81 105 0 2.0
1.82 105 0 2.0
1.83 105 0 2.0
1.84 102 0 2.0
1.85 98 0 1.9
1.86 92 0 1.8
1.87 88 6 1.7
1.88 83 7 1.7
1.89 84 8 1.7
1.9 81 12 1.6
1.91 78 13 1.6
1.92 75 12 1.5
1.93 72 13 1.5
1.94 68 11 1.4
1.95 67 10 1.4
1.96 66 10 1.3
1.97 64 9 1.3
1.98 62 9 1.3
1.99 62 9 1.3
2.0 62 7 1.2


Those you are familiar with antennas will see that the above figures
in no way
represent those of a dummy load


I've seen light bulbs act the same way
when rf was fed to them.
How many people do you know that use a light
bulb as an antenna?
I used one as a dummy load when I was a novice.
It was enlightening, I have to admit that... :/


While listening to Europe coming in with 5/9 signasl,
I thought that everybody should be using "dummy loads"
Art


one anecdote does not a good antenna make.



Art Unwin April 5th 08 12:13 AM

Antenna physical size
 
On Apr 4, 5:51 pm, "Dave" wrote:
"Art Unwin" wrote in message

...



On Apr 4, 4:01 pm, wrote:
On Apr 4, 9:22 am, Art Unwin wrote:


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


I already own a flashlight. Several in fact.


I thought I would share with you my readings on the 160 M band
They are in order as follows Freq, resistance, reactance swr


1.8 105 0 2.1
1.81 105 0 2.0
1.82 105 0 2.0
1.83 105 0 2.0
1.84 102 0 2.0
1.85 98 0 1.9
1.86 92 0 1.8
1.87 88 6 1.7
1.88 83 7 1.7
1.89 84 8 1.7
1.9 81 12 1.6
1.91 78 13 1.6
1.92 75 12 1.5
1.93 72 13 1.5
1.94 68 11 1.4
1.95 67 10 1.4
1.96 66 10 1.3
1.97 64 9 1.3
1.98 62 9 1.3
1.99 62 9 1.3
2.0 62 7 1.2


Those you are familiar with antennas will see that the above figures
in no way
represent those of a dummy load


I've seen light bulbs act the same way
when rf was fed to them.
How many people do you know that use a light
bulb as an antenna?
I used one as a dummy load when I was a novice.
It was enlightening, I have to admit that... :/


While listening to Europe coming in with 5/9 signasl,
I thought that everybody should be using "dummy loads"
Art


one anecdote does not a good antenna make.


I put that out to catch a juicy trout but instead I

captured two croutchy crabs

Richard Clark April 5th 08 12:39 AM

Antenna physical size
 
On Fri, 4 Apr 2008 15:15:51 -0700 (PDT), Art Unwin
wrote:

While listening to Europe coming in with 5/9 signasl,
I thought that everybody should be using "dummy loads"


Hi Arthur,

My pocket radio can do better than that. You haven't given us any
signal reports from other stations listening to you from Europe.

73's
Richard Clark, KB7QHC

Art Unwin April 5th 08 06:14 PM

Antenna physical size
 
On Apr 5, 10:40 am, "Jimmie D" wrote:
wrote in message

...



On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either
case you
are fighting a losing battle.


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


Enlightenment will surely come if Art connects that antenna to the KW amp he
claims to have.

Go back to Art discription of his antenna.IT sounds to me as if it evolved
from a double bazooka.

Make a bazooka antenna with these mods:
.
Forget about the ladder line part of the dipole and make it all like the
center coax section.

Replace the coax section with lamp cord

Now make it fit in a couple of shoe boxes by coiling it all up.

Isnt this a good discription of Art's antenna?

Jimmie


Oh my! My antenna has been revealed to allI .
You just can't stop progress from inquisitive eyes
Now Jimmy, go ahead and make that antenna
and surprise the World
Art

Michael Coslo April 7th 08 06:49 PM

Antenna physical size
 
Art Unwin wrote:
On Apr 4, 3:24 pm, Michael Coslo wrote:
wrote:
On Apr 4, 7:02 pm, "Dave" wrote:
You are thinking wrong.
you might as well plonk him, he is either a persistent troll or totally
convinced that only he has the proper view of the world. in either case you
are fighting a losing battle.
Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.

And always will be, just like modern washday miracles and Dishwashers
that don't leave spots on glasses. ;^)

An open mind does not mean suspension of all disbelief....

- 73 de Mike N3LI -


Mike, you asked for a lot of details about the antenna such
that I thought you were going to make one. What happened
I expected you to come forward with confirmation in a lot of areas!
I thought you were a doer not a talking head.


I'm indeed looking into this.

But sometimes I get a little interested when people invoke the "closed
mind" statement.

- 73 de Mike N3LI -

Richard Harrison April 8th 08 04:21 AM

Antenna physical size
 
Art wrote:
"Oh my! My antenna has been revealed to all."

Size matters and so does the power fed to an antenna. The laws of
physics can`t be violated.

King Mimno & Wing say on page 300 of "Thansmission Lines Antennas and
Wave Guides":

"---a radio wave originates in a systematic mass movement of many
millions of electrons all guided in the same general path and executing
related motions."

Best regards, Richard Harrison, KB5WZI


Richard Harrison April 8th 08 09:03 AM

Antenna physical size
 
Art wrote:
"Where must the "curl" vector be placed in general to justify the right
angle radiation statement that all your books apparently parrot?"

Look up divergence and curl for yourself as I have no special characters
on my keyboard and I am a lousy typist too. You can find what you seek
in the chapter on Maxwell`s equations in ITT`s handbook "Reference Data
for Radio Engineers" This starts on page 43-1 in my 5th edition.

No contradiction to Kraus or Terman is to be found. The right or left
hand rules are good. Magnetic lines of force encircle the current and
electric lines are perpendicular to them as they begin and end on the
wire in their radial attachments. Both fields are at right angles to
each other and both are also at right angles to the current flow.

There is no abberation for diamagnetic materials. The fields are the
same if the wire is lead instead of copper. Diamagnetic distortion is a
myth. Velocity and loss are hardly different. You need to coat the
conductor with a diecectric if you would get more wavelength in a given
length of wire.

Best regards, Richard Harrison, KB5WZI


Richard Harrison April 8th 08 10:37 PM

Antenna physical size
 
Art wrote:
"But ham radio and the Navy have proved him (Terman) wrong with T2FD
testing."

Art has likely tried a VHF or UHF antenna by rotation within a linearly
polarized wavefront. If so, he has experienced cross-polarization and
noted about 20 dB loss when cross-polarized in the field.

My WW-2 navy ship used a Marconi (inverted L) antenna for HF
communications with a Collins TCS. A signal reflected by the ionosphere
gains random polarization in the process. The vertically polarized
Marconi does well with a ground wave over short distances even at HF
over sea water. We had no slopers. The VHF and UHF antennas were all
vertical whips to cover all azimuths. Art`s inclined antenna is in
general a myth.

For rntertainment, we had a broadcast receiver called the RBO. It too
used a Marconi antenna as all medium wave broadcasts are launched from
vertical antennas. It worked well as would be expected of a broadcast
receiver.

Best regards, Richard Harrison, KB5WZI


[email protected] April 14th 08 04:50 AM

Antenna physical size
 
On Apr 14, 10:24 am, "Jimmie D" wrote:
"Jimmie D" wrote in message

...





wrote in message
...


On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or
totally
convinced that only he has the proper view of the world. in either
case you
are fighting a losing battle.


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


Enlightenment will surely come if Art connects that antenna to the KW amp
he claims to have.


Go back to Art discription of his antenna.IT sounds to me as if it evolved
from a double bazooka.


Make a bazooka antenna with these mods:
.
Forget about the ladder line part of the dipole and make it all like the
center coax section.


Replace the coax section with lamp cord


Now make it fit in a couple of shoe boxes by coiling it all up.


Isnt this a good discription of Art's antenna?


Jimmie


I had a couple of 100 ft rolls of speaker wire on cardboard reels so I
decided to connect them together as Art had described and they give VSWR
indication much as he described even if I stick them in a metal locker. This
may be just what a lot of hams are looking for as it is a very quiet
antenna.

Jimmie


g'day Jimmy

welcome to the minority and stand by for Richard to call you a
fool and stupid for listening to Art, I am sure you are the first
among many who will now build the antenna and find out for themselves
instead of listening to those who say if it is not in a book it cant
be done
well done.

Derek



[email protected] April 14th 08 06:46 AM

Antenna physical size
 
On Apr 14, 11:50 am, wrote:
On Apr 14, 10:24 am, "Jimmie D" wrote:



"Jimmie D" wrote in message


...


wrote in message
...


On Apr 4, 7:02 pm, "Dave" wrote:


You are thinking wrong.


you might as well plonk him, he is either a persistent troll or
totally
convinced that only he has the proper view of the world. in either
case you
are fighting a losing battle.


Two perfect examples of a closed mind, but not to worry
enlightenment will be along shortly.


Derek


Enlightenment will surely come if Art connects that antenna to the KW amp
he claims to have.


Go back to Art discription of his antenna.IT sounds to me as if it evolved
from a double bazooka.


Make a bazooka antenna with these mods:
.
Forget about the ladder line part of the dipole and make it all like the
center coax section.


Replace the coax section with lamp cord


Now make it fit in a couple of shoe boxes by coiling it all up.


Isnt this a good discription of Art's antenna?


Jimmie


I had a couple of 100 ft rolls of speaker wire on cardboard reels so I
decided to connect them together as Art had described and they give VSWR
indication much as he described even if I stick them in a metal locker. This
may be just what a lot of hams are looking for as it is a very quiet
antenna.


Jimmie


g'day Jimmy

welcome to the minority and stand by for Richard to call you a
fool and stupid for listening to Art, I am sure you are the first
among many who will now build the antenna and find out for themselves
instead of listening to those who say if it is not in a book it cant
be done
well done.

Derek


g'day Jimmie

Miss spelt your name my apologies.

Derek


Richard Clark April 14th 08 06:47 AM

Antenna physical size
 
On Sun, 13 Apr 2008 20:50:04 -0700 (PDT), wrote:

I had a couple of 100 ft rolls of speaker wire on cardboard reels so I
decided to connect them together as Art had described and they give VSWR
indication much as he described even if I stick them in a metal locker. This
may be just what a lot of hams are looking for as it is a very quiet
antenna.


welcome to the minority and stand by for Richard to call you a
fool and stupid for listening to Art, I am sure you are the first
among many who will now build the antenna and find out for themselves
instead of listening to those who say if it is not in a book it cant
be done
well done.


How droll!

Perhaps one day you will be able to tell those who are laughing up
their sleeve at this.

Seeing as you are clueless to the implications of this report, I
return to my original question, Derek:
Why are you here?

73's
Richard Clark, KB7QHC

[email protected] April 14th 08 10:20 AM

Antenna physical size
 
On Apr 14, 12:47 am, Richard Clark wrote:
On Sun, 13 Apr 2008 20:50:04 -0700 (PDT), wrote:
I had a couple of 100 ft rolls of speaker wire on cardboard reels so I
decided to connect them together as Art had described and they give VSWR
indication much as he described even if I stick them in a metal locker. This
may be just what a lot of hams are looking for as it is a very quiet
antenna.

welcome to the minority and stand by for Richard to call you a
fool and stupid for listening to Art, I am sure you are the first
among many who will now build the antenna and find out for themselves
instead of listening to those who say if it is not in a book it cant
be done
well done.


How droll!

Perhaps one day you will be able to tell those who are laughing up
their sleeve at this.

Seeing as you are clueless to the implications of this report, I
return to my original question, Derek:
Why are you here?

73's
Richard Clark, KB7QHC


Probably one of Arts relatives...
It does boggle the mind.. Jimmie gives a report which seems
to indicate it's performance does indeed mimic an air cooled
dummy load, and ole Derek thinks the report claims a success
of the design as an antenna intended to radiate RF.
Cinderella has a mustache, green teeth, and hairy legs
it seems. :(

I'd bet this lack of noise pertains to most any direction and
angle too..
IE: you could spin it round and round, and the noise received
will be puny in any direction compared to any real antenna.
It's possible the pattern may have a couple of nulls where
the noise gets even lower if received from a single source. :/
Art has reinvented the dummy load. And a fairly poorly
designed one at that.. :{
Woe is Art.





JIMMIE April 17th 08 12:29 AM

Antenna physical size
 
On Apr 14, 10:47*am, "Jimmie D" wrote:
wrote in message

...





On Apr 14, 12:47 am, Richard Clark wrote:
On Sun, 13 Apr 2008 20:50:04 -0700 (PDT), wrote:
I had *a couple of 100 ft rolls of speaker wire on cardboard reels so
I
decided to connect them together as Art had described and they give
VSWR
indication much as he described even if I stick them in a metal
locker. This
may be just what a lot of hams are looking for as it is a very quiet
antenna.
* *welcome to the minority and stand by for Richard to call you a
fool and stupid for listening to Art, I am sure you are the first
among many who will now build the antenna and find out for themselves
instead of listening to those who say if it is not in a book it cant
be done
* well done.


How droll!


Perhaps one day you will be able to tell those who are laughing up
their sleeve at this.


Seeing as you are clueless to the implications of this report, I
return to my original question, Derek:
* * * * Why are you here?


73's
Richard Clark, KB7QHC


Probably one of Arts relatives...


Probably a sock puppet- Hide quoted text -

- Show quoted text -


I made a small mod to Arts design that greatly improved it as a
receiving antenna, I didnt care to risk my finals or melt down a
couple of rolls of lamp cord. I connected both leg of the feedline to
a single banana plug
and connected this to my aerial input

[email protected] April 17th 08 12:16 PM

Antenna physical size
 
That almost makes sense, so, it has to be cheating.
- 'Doc



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