On Nov 21, 2:00*pm, Art Unwin wrote:
On Nov 21, 10:51*am, Art Unwin wrote:





On Nov 21, 9:52*am, John Smith wrote:

Art Unwin wrote:
...
Seems to me you are recommending the "?slinky" !
Is that correct?
Art

I believe, he is speaking of rotating the flat surfaces of the
conductor(s) 90 degrees to what a "slinkys'" orientation places them at.

In which case, "mondo-capacitive loading to the 'environment'" is also
introduced ... while minimizing capacitive loading between turns.

Regards,
JS

Wouldn't that take more room than a slinky per turn?
His attic is very small!.I think he would be much better placing the
turns as close together as possible
to obtain axial directivity. The only mod required to the slinky is to
ensure the number of right hand turn loop
are equal to the number of left *hand turned loops. Feed could still
be at the center and depending on the amount
of wire used it would radiate like a dipole or axially. What this does
is cancel the lumped loads created in manufacture which
Wim suggests is a problem ie the two supposedly lumped loads will
cancel
*such that you have several wavelengths of wire helix style and no or
repetitive points of none *reactive impedances. He could ofcourse
place
the windings in a vertical direction to obtain an omnidirectional
pattern and utilise the available room to a maximum.
A lot depends on what frequencies he wishes to use as to what form the
radiator becomes.
Best regards
Art

I forgot to mention that a similar type radiator is shown in Antenna
Applications
Reference Guide by Johnson and Jasik with slight modification. This
design was succeeded by the helix antenna
to obtain circular polarization which is now universal with respect to
space communications.
The beauty of this design is the multiplicity of resonant points and
the use of different frequencies.
*The economy of space is some what altered by the need of multi
wavelength of wire because
of slow wave.but then it enables axial directivity. There are many
hams who are delighted by the slinky performance
and they are still sold in huge numbers to the ham community, so it
must be performing!
Art Unwin- Hide quoted text -

- Show quoted text -

Art, where did you get the idea a slinky had "axial directivity" at
40M. I hazard a guess that it was from reading about helix antennas.
The axial radiation is only true if the diameter of the helix is
fairly large, on the order of 1/pi wavelength usually.
This would be a huge antenna if designed for the frequency(40M) that
the OP was asking.
I can see how this misunderstanding led you to your shoebox
antenna.design.

Gee I hope you arent spending good money filing for a patent on that
thing. I understand that can cost a couple of thousand these days.
However it would be interesting to see you get it.

Jimmie

On Nov 21, 3:00*pm, JIMMIE wrote:
On Nov 21, 2:00*pm, Art Unwin wrote:



On Nov 21, 10:51*am, Art Unwin wrote:

On Nov 21, 9:52*am, John Smith wrote:

Art Unwin wrote:
...
Seems to me you are recommending the "?slinky" !
Is that correct?
Art

I believe, he is speaking of rotating the flat surfaces of the
conductor(s) 90 degrees to what a "slinkys'" orientation places them at.

In which case, "mondo-capacitive loading to the 'environment'" is also
introduced ... while minimizing capacitive loading between turns.

Regards,
JS

Wouldn't that take more room than a slinky per turn?
His attic is very small!.I think he would be much better placing the
turns as close together as possible
to obtain axial directivity. The only mod required to the slinky is to
ensure the number of right hand turn loop
are equal to the number of left *hand turned loops. Feed could still
be at the center and depending on the amount
of wire used it would radiate like a dipole or axially. What this does
is cancel the lumped loads created in manufacture which
Wim suggests is a problem ie the two supposedly lumped loads will
cancel
*such that you have several wavelengths of wire helix style and no or
repetitive points of none *reactive impedances. He could ofcourse
place
the windings in a vertical direction to obtain an omnidirectional
pattern and utilise the available room to a maximum.
A lot depends on what frequencies he wishes to use as to what form the
radiator becomes.
Best regards
Art

I forgot to mention that a similar type radiator is shown in Antenna
Applications
Reference Guide by Johnson and Jasik with slight modification. This
design was succeeded by the helix antenna
to obtain circular polarization which is now universal with respect to
space communications.
The beauty of this design is the multiplicity of resonant points and
the use of different frequencies.
*The economy of space is some what altered by the need of multi
wavelength of wire because
of slow wave.but then it enables axial directivity. There are many
hams who are delighted by the slinky performance
and they are still sold in huge numbers to the ham community, so it
must be performing!
Art Unwin- Hide quoted text -

- Show quoted text -

Art, where did you get the idea a slinky had "axial directivity" at
40M. I hazard a guess that it was from reading about helix antennas.
The axial radiation is only true if the diameter of the helix is
fairly large, on the order of 1/pi wavelength usually.
This would be a huge antenna if designed for the frequency(40M) that
the OP was asking.
I can see how this misunderstanding led you to your shoebox
antenna.design.

Gee I hope you arent spending good money filing for a patent on that
thing. I understand that can cost a couple of thousand these days.
However it would be interesting to see you get it.

Jimmie

Jimmie
The diameter of the helix and the pitch of the helix is only a couple
of terms that Krauss applied to a helix antenna which is not in
equilibrium.
He also assumed too much when he assigned more gain to a helix that
could be attained by a antenna not in equilibrium which I strongly
suspect is the belief he had in the displacement current. Krauss did a
lot of pioneering work but the passage of time have pointed to many
errors.
If a helix winding wire is less than a couple of wavelengths then the
radiation will be at right angle to the axis. If the wire length is
above two WL preferably 7-10 WL the radiation peak will be axial
regardless of the diameter or helix angle as long as the radiator is
in a state of equiulibrium. the law that I continually state from the
extension of the Gaussian law of statics which I derived. Wind two
inductors with a common wire but wound in opposite directions and view
with MFJ 259 or alternatively review ARRL publications where they show
a fully wound dipole and then start thinking for yourself instead of
jumping to unfounded conclusions. I also read that the reason that the
EH antenna and the cross field antenna does not work as expected
because they were founded in part on the non existant displacement
current b ut I have not followed up on that from first principles so
it is just a statement
Art

Art Unwin wrote:

...
Wouldn't that take more room than a slinky per turn?
His attic is very small!.I think he would be much better placing the
turns as close together as possible
to obtain axial directivity. The only mod required to the slinky is to
ensure the number of right hand turn loop
are equal to the number of left hand turned loops. Feed could still
be at the center and depending on the amount
of wire used it would radiate like a dipole or axially. What this does
is cancel the lumped loads created in manufacture which
Wim suggests is a problem ie the two supposedly lumped loads will
cancel
such that you have several wavelengths of wire helix style and no or
repetitive points of none reactive impedances. He could ofcourse
place
the windings in a vertical direction to obtain an omnidirectional
pattern and utilise the available room to a maximum.
A lot depends on what frequencies he wishes to use as to what form the
radiator becomes.
Best regards
Art

Art:

The way I "read" him is, he now has a 1m loop, SINGLE TURN (equiv. to
resonating a 8-12+ ft. whip on the hf bands?) able to do 10-30m--with
WHATEVER "matchbox" he is choosing to run ... he is contemplating on
adding a second 1m turn (to add 40m capabilities, apparently) ... are we
on the same page? ... and, loops are NEVER omni-directional! Well,
other than one constructed to radiate/receive in the plane of the loop
and run in a horizontal plane, would, perhaps, do some type of
omni-horizontal-polarization?--and a 1m at 10-30m, it ain't such an
animal! (well, maybe-kinda-sorta, but I DON'T KNOW! I would have to get
hands-on-experience before trusting a ventured reply ... any books I
have ever laid hands on are vague on all this ... )

Personally, the only time I have ever used a loop is for AM broadcast
radio and direction finding (fox hunts) in the 10 to 2m bands, and, I
did NOT want omni capabilities! ... well, there may have been one or
two--but so long ago they escape memory ... I never did "like them."

Or, in other words, I am NOT a "loop guru" ... :-(

Anyway, after all that verbiage, the cut-to-the-chase: "I would think a
slinky and what he has are two 'different species'."

Regards,
JS

"Art Unwin" wrote in message
...
the law that I continually state from the
extension of the Gaussian law of statics which I derived.

you haven't presented anything that you derived... state the equation.

On Nov 21, 3:50*pm, John Smith wrote:
Art Unwin wrote:
...
Wouldn't that take more room than a slinky per turn?
His attic is very small!.I think he would be much better placing the
turns as close together as possible
to obtain axial directivity. The only mod required to the slinky is to
ensure the number of right hand turn loop
are equal to the number of left *hand turned loops. Feed could still
be at the center and depending on the amount
of wire used it would radiate like a dipole or axially. What this does
is cancel the lumped loads created in manufacture which
Wim suggests is a problem ie the two supposedly lumped loads will
cancel
*such that you have several wavelengths of wire helix style and no or
repetitive points of none *reactive impedances. He could ofcourse
place
the windings in a vertical direction to obtain an omnidirectional
pattern and utilise the available room to a maximum.
A lot depends on what frequencies he wishes to use as to what form the
radiator becomes.
Best regards
Art

Art:

The way I "read" him is, he now has a 1m loop, SINGLE TURN (equiv. to
resonating a 8-12+ ft. whip on the hf bands?) able to do 10-30m--with
WHATEVER "matchbox" he is choosing to run ... he is contemplating on
adding a second 1m turn (to add 40m capabilities, apparently) ... are we
on the same page? ... and, loops are NEVER omni-directional! *Well,
other than one constructed to radiate/receive in the plane of the loop
and run in a horizontal plane, would, perhaps, do some type of
omni-horizontal-polarization?--and a 1m at 10-30m, it ain't such an
animal! (well, maybe-kinda-sorta, but I DON'T KNOW! *I would have to get
hands-on-experience before trusting a ventured reply ... any books I
have ever laid hands on are vague on all this ... )

Personally, the only time I have ever used a loop is for AM broadcast
radio and direction finding (fox hunts) in the 10 to 2m bands, and, I
did NOT want omni capabilities! ... well, there may have been one or
two--but so long ago they escape memory ... I never did "like them."

Or, in other words, I am NOT a "loop guru" ... :-(

Anyway, after all that verbiage, the cut-to-the-chase: *"I would think a
slinky and what he has are two 'different species'."

Regards,
JS

I stated Slinky only because I thought that was what Wim was proposing
and then went from there
If the poster now has a loop without a capacitor that is resonant on
40M then a second loop wound
in the opposite direction when added to the other loop. If he is
adding a lumped load in the form
of a capaciter then all bets are off as Maxwell doesn't entertain
lumped loads in his equations.
Art

Art Unwin wrote:

...
If the poster now has a loop without a capacitor that is resonant on
40M then a second loop wound
in the opposite direction when added to the other loop. If he is
adding a lumped load in the form
of a capaciter then all bets are off as Maxwell doesn't entertain
lumped loads in his equations.
Art

What? You can't read/think?

I don't believe he said anything near that ... indeed, I took for
granted he said something almost opposite to what you "intuit" with you,
apparent, psychic powers?

Did you evoke or invoke all these visions?

Regards,
JS

Art Unwin wrote:

...
If the poster now has a loop without a capacitor that is resonant on
40M then a second loop wound
in the opposite direction when added to the other loop. If he is
adding a lumped load in the form
of a capaciter then all bets are off as Maxwell doesn't entertain
lumped loads in his equations.
Art

What? You can't read/think?

I don't believe he said anything near that ... indeed, I took for
granted he said something almost opposite to what you "intuit" with
your, apparent, psychic powers?

Did you evoke or invoke all these visions?

Regards,
JS

On 21 nov, 16:44, Art Unwin wrote:
On Nov 21, 5:38*am, Wimpie wrote:



On 21 nov, 04:47, Steve wrote:

I've seen several programs that will help you calculate the precise
dimensions of a single-turn loop, given the composition of the
radiating element, its thickness, and so on. However, none of these
programs are written to cover the case of a two or more-turn loop.

Does anyone know of a program that will offer guidance in the
construction of a two or more-turn loop?

Thanks,

Steve

Hello Steve,

You probably did some loop calculations and found that in a transmit
case the voltage across the tuning capacitor is very high (and
bandwidth is limited). Also for small loops, most input power is lost
as heat due to copper resistance.

When you make a two turn loop, the radiation resistance will increase
with factor 4. So with half the current through the loop, the radiated
power is same (as for a single turn loop). *When the 2 turns of the
loop are relative close together, the inductance increases with factor
4, hence the reactance.

The current has been halved, but because of the reactance, the voltage
across the tuning capacitance will be 2 times the value for the single
turn loop with higher probability on corona effects. *An advantage can
be an almost 4 times smaller tuning capacitor.

One may expect that the loss resistance due to heat of a two-turn
inductor will be twice as high (w.r.t. single turn case). This is not
true; the loss resistance will be more then twice as high because of
proximity effect. The current will not equally distribute along the
circumference of the tube/wire. *So the efficiency of the loop will be
less then twice as high (w.r.t. single turn case).

When the turns are far apart (with respect to wire/tube diameter),
inductance will not be 4 times higher and proximity effect will be
less. You will get better performance than the single turn loop made
of same diameter tube/wire. The result will be the same as when you
place the two turns in parallel. Inductance will decrease somewhat
(hence lower voltage across capacitor), AC resistance also, hence
radiation efficiency).

There is an "however". When you make a single turn loop from flat
strip that has the same width as the length of your two-turn loop, you
will notice: *1. reduced AC resistance (because of the significantly
larger circumference of the flat strip with respect to a thin round
tube, 2. inductance will decrease (H field lines have to take a longer
path around the wide strip), 3. radiation resistance will not change
with respect to a single turn loop from wire/tube.
This results in higher efficiency and increased bandwidth. * The
overall result will be better then for your two-turn loop. I think
that is the reason why most programs are for single turn loops.

So for the transmit case, given fixed diameter of your loop, the
larger the copper surface (=length*circumference), the better the
efficiency. *Best thing to enhance conductor surface is to use very
wide flat strip (high wind load), or multiple wires (with some spacing
in between) in parallel (limited wind load).

Off course for the receive-only case, a multi turn loop can be helpful
as you can use a smaller tuning capacitor.

Best regards,

Wim
PA3DJSwww.tetech.nl
In case of PM, don't forget to remove abc.

Seems to me you are recommending the "?slinky" !
Is that correct?
Art

Sorry Art, I am not talking about a slinky.

I am just talking about a multi turn (2 turns) loop where overall wire
length is 0.25 lambda so you can assume that current in wire is
constant along the length. It must be tuned by external capacitance.

Regarding the strip. When you take a 3.14m long 20cm wide thin copper
strip and make a loop of it (1m diameter), it will have a better
efficiency then when you take 6.28m copper tubing with Dtube=2cm and
make a two-turn loop (Dloop=1m, turns 18 cm apart).

In the strip case, the current has more circumference to flow (40cm)
instead of 6.28cm for the copper tubing. AC resistance of copper
tubing will be about 10 times higher. Off course, current in two-turn
loop will be half (for same radiated power), but still heat losses
will be 10*0.5^2=2.5 times higher (for the two-turn loop).

When both loops have good efficiency (so radiation resistance
dominates), the strip loop will have better bandwidth as flux path is
longer and therefore results in less inductance.

I hope this clarifies my posting.

Best regards,

Wim
PA3DJS
Please remove abc in case of PM.

On Nov 21, 4:07*pm, "Dave" wrote:
"Art Unwin" wrote in message

...

the law that I continually state from the
extension of the Gaussian law of statics which I derived.

you haven't presented anything that you derived... state the equation.

Oh come on David I do not work for you, do it for yourself as you have
a superior background than I do.
If you are proficient in mathematics check out the addition of
displacement current of Maxwell and review it as just that.
a current in circular foirm that DOES generate a displacement
magnetic field such that it displaces a charged particle
from the surface of the radiator. This eddy current has the units of
current which somehow would match the
description of the "weak force:". Maybe the other masters needed to
include this same addition If your math is up to it
why not check that out? You stated previously that you wanted to know
where the weak current equation is so, now you can start on a series
of
removal or added equation to all the formulas supplied to Maxwell by
previous masters and determine for yourself,. The correct units are
there
so that all equations jive with each other sfter manipulating the
supplied laws.
Stae equation you ask? A radiator can be any shape, size or elevation
when providing the maximum radiation as long as it is in equilibrium.
I believe that the helix goes along way in supporting that statement
which comes from changing a static field to a dynamic field and
confirmed by existing antenna programs based ion Maxwell';s work.
Ofcourse you can declare antenna computer programs are in error and
salvage your credability or place such a statement in the practicable
book that you are writing! After all if it is printed in a book it
must be right.......right?
Art Unwin KB9MZ.......XG....(UK)(

On Nov 21, 5:10*pm, John Smith wrote:
Art Unwin wrote:

* ...

If the poster now has a loop without a capacitor that is resonant on
40M then a second loop wound
in the opposite direction when added to the other loop. If he is
adding a lumped load in the form
*of a capaciter then all bets are off as Maxwell doesn't entertain
lumped loads in his equations.
Art

What? *You can't read/think?

I don't believe he said anything near that ... indeed, I took for
granted he said something almost opposite to what you "intuit" with you,
apparent, psychic powers?

Did you evoke or invoke all these visions?

Regards,
JS

Maybe I was to quick in replying. Hope I haven't ruined your week end.
My car battery went down so I filled it with distilled water and tried
to charge it
But the meter on the charger is not working/moving so I am not sure if
it is charging,
Strike the two charger together and get a spark but the weather is
below freezing
Don't know what to do now. I am confused Maybe the water is frozen