Loading Coils; was : Vincent antenna
 

On Fri, 7 Dec 2007 14:53:09 -0800 (PST), art
wrote:
Somebody somewhere has obviously postulated that gravitational
forces are every where which puts science back in the stone
ages.

Hi Art,

It was some schlemiel called Isaac Newton.

He offered a very simple equation you probably are not familiar with:
G times the Mass of Body A time the Mass of Body B
divided by
distance between them squared

This English clown's theory was put into a cocked hat by Einstein - so
you two have something in common!

73's
Richard Clark, KB7QHC

Loading Coils; was : Vincent antenna
 

Michael Coslo wrote:

...
It is a well know scientific fact the only true aphrodisiac is a man
doing housework.

- 73 de Mike N3LI -

Hmmm, I differ, my wife will trade work for sex--but only if I do the
work. I don't then an "aphrodisiac effect" is at play though ... LOL

Regards,
JS

Loading Coils; was : Vincent antenna
 

John Smith wrote:

...
I don't think an "aphrodisiac effect" is at play though ... LOL
...

Hmmm, the 20mg Hydrocodone has more of a "kick" than I realize.

Regards,
JS

Loading Coils; was : Vincent antenna
 

On 7 Dec, 16:46, Richard Clark wrote:
On Fri, 7 Dec 2007 14:53:09 -0800 (PST), art
wrote:

Somebody somewhere has obviously postulated that gravitational
forces are every where which puts science back in the stone
ages.

Hi Art,

It was some schlemiel called Isaac Newton.

He offered a very simple equation you probably are not familiar with:
G times the Mass of Body A time the Mass of Body B
divided by
distance between them squared

This English clown's theory was put into a cocked hat by Einstein - so
you two have something in common!

73's
Richard Clark, KB7QHC

I did not know that equation. Einstein said a lot of things and
was often proved in error. Did he mention equilibrium or the
other laws like:
Every action has an equal and opposite reaction? For that matter
how many laws of Newton did he put down?
Any idea where I can read up on that and how he arrived at that
conclusion? Seems odd that we have so many gravity centers in this
universe and a neutral point never occurs.....anywhere.
Some of those stationary things in the sky must be holding on to a
piece of string tied to the moon
No. I do not have any books on Einstein but do have Planck and
I don't recall him mentioning that.Is it just called Einsteins Law
of ???????
Art
Oh, and another thing why are you injecting the word "clown"?
Are you reverting to your old tricks or did you just slip up?

Loading Coils; was : Vincent antenna
 

On Dec 7, 4:09 pm, Cecil Moore wrote:
Keith Dysart wrote:
So sometimes a 600 to 100 ohm discontinuity
produces a 36.6 degree phase shift and sometimes
it produces a 22.7 degree phase shift (and probably
any value in between).

Yes, of course - nobody said the phase shift wasn't
a variable. Why would you expect it to be a constant?
It is a variable that depends upon the phase of the
component forward and reflected waves.

I suggest that "work[ing] up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143" will
not be useful for predicting the phase shift.

It will be useful for reporting that particular phase
shift. If other conditions change, that phase shift
will change. What is unexpected about that?

You implied that you were going to compute it
using just rho, which would mean it would be
constant for any pair of impedances.

With more inputs, it might be possible to
compute a number that, when added to the
actual electrical lengths of the lines, will
result in 90 degrees. I expect the algorithm
to be fairly complicated.

Of course, one can always just say it is equal
to 90 minus the sum of the electrical lengths
of the lines, though if there were two or more
impedance discontinuities, it might be difficult
to apportion the difference between them.

I await the algorithm.

....Keith

Loading Coils; was : Vincent antenna
 

On Dec 7, 4:10 pm, Cecil Moore wrote:
Keith Dysart wrote:
Sounds good, but mostly you do not examine
ideal conditions because they tend to show that
the models fail.

I believe that is a false statement. Please
prove your assertion.

The best example was when you refused to discuss
the reflections at the output of an amplifier with a
well defined output impedance because a typical
amateur transmitter does not have a well defined
output impedance.

The discussion was going to demolish the idea of
complete re-reflection at the output of a transmitter
but stalled because you refused to use the simple
case to examine the issue. Using the more
complicated scenario of a real transmitter it was
much easier to obfuscate with the result that the
discussion went nowhere.

Which was sad because there was much
opportunity for learning there.

....Keith

Loading Coils; was : Vincent antenna
 

Keith Dysart wrote:
You implied that you were going to compute it
using just rho, which would mean it would be
constant for any pair of impedances.

No, I did not. Rho can be constant but the phase
angle of the incident voltage changes with
position. Therefore, the phase angle of the
reflected voltage changes with position.

This subject is already covered in my energy
analysis article at:

http://www.w5dxp.com/energy.htm
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Keith Dysart wrote:
The best example was when you refused to discuss
the reflections at the output of an amplifier with a
well defined output impedance because a typical
amateur transmitter does not have a well defined
output impedance.

I tend to avoid discussions about amplifiers because
I know very little about amplifiers, real or imagined.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

On Fri, 7 Dec 2007 18:14:36 -0800 (PST), art
wrote:

I did not know that equation. Einstein said a lot of things and
was often proved in error. Did he mention equilibrium or the
other laws like:
Every action has an equal and opposite reaction?

Hi Arthur,

Every equation describes equilibrium, by definition.

For that matter
how many laws of Newton did he put down?

All of them.

Any idea where I can read up on that and how he arrived at that
conclusion? Seems odd that we have so many gravity centers in this
universe and a neutral point never occurs.....anywhere.

Not so. A simple example is called the "Trojan points."

Some of those stationary things in the sky must be holding on to a
piece of string tied to the moon

Well, given the moon moves, the string must move whatever is tied to
it. In short, there is nothing stationary anywhere.

No. I do not have any books on Einstein but do have Planck and
I don't recall him mentioning that.Is it just called Einsteins Law
of ???????

General relativity.

73's
Richard Clark, KB7QHC

Loading Coils; was : Vincent antenna
 

AI4QJ wrote:
"art" wrote in message
...

In fact the law
of
statics is based on gravitational field which extends to what
Gauss called the limits of gravitational effects.
Quite a few other laws are based on similar logic

Art Unwin KB9MZ.....XG(uk)

What is the mass of 1 Volt/meter?



Actually, you can store energy in an electrical field easily enough; ask
any capacitor. And energy has a mass equivalent. It may not be much, but
it isn't zero. This probably isn't what Art means, though. If you
thought about his post deeply enough, and in just the right way, you'd
see what he's getting at. Smart ass questions aren't helpful. Not that
I'm agreeing with Art. I'm not. But if you want to understand, as
opposed to just being sarcastic, you'll have to train your mind to
operate the way his does. Cecil, on the other hand, wants to argue,
so his posts aren't as much fun, but he does write some entertaining
things on occasion, and his theories are tolerable enough as long as you
realize they're all quite wrong.
73,
KA6RUH

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
Keith Dysart wrote:
You have done this before; postulating
explanations that only work in the complexity
of the "real" world, but fail when presented with
the simplicity of ideal test cases.

For Pete's sake, Keith, Ohm's law doesn't even
work when R=0.

Then, when the explanations fail on the simple
cases, claiming these cases are not of interest
because the real world is more complex.

I define the boundary conditions within which my
ideas work. Whether they work outside those defined
conditions is irrelevant. I believe they do work
for ideal conditions, but I don't have the need
to prove a "theory of everything".

Every model that we use has flaws. Asking me to
come up with a flawless "theory of everything"
model is an obvious, ridiculous diversion but
you already know that.

This isn't a diversion: it's the core of the whole dispute.

These days, mathematical models are the normal, everyday way that
engineers go about their business. A bedrock principle is that if a
model is going to be usable and trustworthy, it MUST join up correctly
with existing knowledge. Your model can be as elaborate as you like, but
it always has to prove itself against the simple cases that we already
know about.

Anyone with experience knows that these "simple" reality tests are the
most often the hardest for an elaborate model to pass... but that
doesn't excuse them from the test. If a model cannot handle the simple
situations that we do understand, we can never trust it in more complex
situations.

Ohm's law is a perfect example of a model that works. The whole point is
that Ohms' law IS a good model of reality for a very wide range of
situations, including the simple but extreme case where R equals
exactly zero. It's absurd to suggest that there's a glitch - it simply
means that V would be exactly zero too.

Likewise there are no glitches in the standard circuit models for
inductance and capacitance. They work just fine, for all cases where the
dimensions of the circuit are very small with respect to the wavelength,
so that distributed effects and radiation are negligible. Where those
assumptions are no longer accurate, we can extend the simple model to
include some corrections. But the most important point is, we always
know that we're building up from a solid foundation.

That is also the sensible way to think about loaded antennas. Calculate
it the simple way first, assuming lumped inductive loading, and then
apply corrections as necessary. As I've said before, this simple, solid
method is the one that works. It can take you straight to a workable
prototype, which can be quickly adjusted to frequency. Countless authors
have demonstrated how to do this, and anyone can download G4FGQ's
MIDLOAD program to do the same.

While other people choose to build on those solid foundations, Cecil
insists that simple routine reality tests are a "diversion". He prefers
to keep his floating castles well clear of such hard rocks.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

Loading Coils; was : Vincent antenna
 

On Dec 8, 12:52 am, Cecil Moore wrote:
Keith Dysart wrote:
The best example was when you refused to discuss
the reflections at the output of an amplifier with a
well defined output impedance because a typical
amateur transmitter does not have a well defined
output impedance.

I tend to avoid discussions about amplifiers because
I know very little about amplifiers, real or imagined.

Serious revisionism here.

You should count your posts on (re)reflections at the
output terminals of amplifiers.

....Keith

Loading Coils; was : Vincent antenna
 

Tom Donaly wrote:
Cecil, on the other hand, wants to argue,
so his posts aren't as much fun, but he does write some entertaining
things on occasion, and his theories are tolerable enough as long as you
realize they're all quite wrong.

Tom, please download this EZNEC file, hit the "Load Dat"
button, and tell us what is "wrong" with the current phase
as reported by EZNEC.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Ian White GM3SEK wrote:
That is also the sensible way to think about loaded antennas. Calculate
it the simple way first, assuming lumped inductive loading, and then
apply corrections as necessary. As I've said before, this simple, solid
method is the one that works. It can take you straight to a workable
prototype, which can be quickly adjusted to frequency. Countless authors
have demonstrated how to do this, and anyone can download G4FGQ's
MIDLOAD program to do the same.

The point is that IT OBVIOUSLY DOESN'T WORK, Ian, for
the delay through a loading coil. If it worked, W8JI
would not have gotten a 3 ns delay through a 2" dia,
100 TPI, 10" long loading coil. If his test setup
looked like mine, he would have measured a valid
delay around 25 ns.

http://www.w5dxp.com/coiltest.gif

Ian, are you afraid to run that test for yourself?

Cecil
insists that simple routine reality tests are a "diversion".

Please don't twist my words. I insist that simple routine
*UNreality* tests are a diversion. But, my personal opinion
doesn't change anything. The model that I am using works. The
model that W8JI is using doesn't work.

Please take a look at: http://www.w5dxp.com/coil512.ez
and tell me why EZNEC disagrees with W8JI's model.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Keith Dysart wrote:
You should count your posts on (re)reflections at the
output terminals of amplifiers.

Conceptually, I know what has to happen based on the
principle of conservation of energy, i.e. all energy
is conserved. If the reflected wave energy is not
entering the source, it is being reflected at the
source. That is all I was saying during those posts.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:


---43.4 deg 600 ohm line---+---10 deg 100 ohm line---open

The Smith Chart does make it clear what is happening.
Here is the math to go with it. The impedance at the
junction of the two lines is:

-j100*tan(90-10) = -j100*tan(80) = -j567 ohms
-j600*tan(43.4) = -j600*tan(43.4) = -j567 ohms

The phase shift at the junction of the two lines is:
80-43.4 = 36.6 degrees

Time permitting, I will work up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143

So how many nanoseconds does that 36.6 degree phase shift represent?

8-)

73,
Gene
W4SZ

Loading Coils; was : Vincent antenna
 

On 7 Dec, 22:25, Richard Clark wrote:
On Fri, 7 Dec 2007 18:14:36 -0800 (PST), art
wrote:

I did not know that equation. Einstein said a lot of things and
was often proved in error. Did he mention equilibrium or the
other laws like:
Every action has an equal and opposite reaction?

Hi Arthur,

Every equation describes equilibrium, by definition.

For that matter
how many laws of Newton did he put down?

All of them.

Any idea where I can read up on that and how he arrived at that
conclusion? Seems odd that we have so many gravity centers in this
universe and a neutral point never occurs.....anywhere.

Not so. A simple example is called the "Trojan points."

Some of those stationary things in the sky must be holding on to a
piece of string tied to the moon

Well, given the moon moves, the string must move whatever is tied to
it. In short, there is nothing stationary anywhere.

No. I do not have any books on Einstein but do have Planck and
I don't recall him mentioning that.Is it just called Einsteins Law
of ???????

General relativity.

73's
Richard Clark, KB7QHC

As with the convergence of energy vectors described
in the Columbian lectures so is general relativity.
Both are procedures that are being followed
in an effort to find a path to GAT. As I stated before
it often is not the destination that counts but what
one learns on the journey . Both of these procedures
have provided insights to the universe but neither
proved to be the answer for Einsteins main quest
which was GAT. Yes, a lot of theories have been produced
by using these procedures some of which relate to our universe
and some of these theories may prove to be correct
but for the wrong reasons. Such was the making of the word
"theory" which deviates from a standard when considering a "law".
If you review Einsteins work in the search of GAT you will
find that most of his theories by his peers which he often
confided in so he is not immune to error.
With respect to the moon and the sun you are quite correct tho
I was being a bit vacitious, but it does show you are capable
of serious debate when you have a mind to together with sufficient
knoweledge to venture into unknown trails of thought, musings
and deduction.
Art Unwin KB9MZ.....xg (uk)

Loading Coils; was : Vincent antenna
 

Gene Fuller wrote:
Cecil Moore wrote:
Time permitting, I will work up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143

So how many nanoseconds does that 36.6 degree phase shift represent?

As far as impedance discontinuity *points* go, a nonsense
question.

How many nanoseconds does it take for a signal to travel
through a dimensionless point???? Well, let's see. What
is the speed of light multiplied by zero? Hmmmm, that's
a really tough one.

At any instant of time the forward voltage on
one side of the discontinuity *point* has a relative phase
difference from the forward voltage on the other side of
the *point*. This relative phase difference is constant as
long as the conditions remain unchanged.

The reason that it takes nanoseconds for a signal to travel
through a 75m Bugcatcher loading coil is that the coil is
NOT a dimensionless point. Mine occupies almost 200 cubic
inches. Loading coils with zero dimensions exist *only* in
the human mind and are impossible in reality.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:

...
http://www.w5dxp.com/coiltest.gif
...


Gesus Cecil!

Beautiful artwork! What'd you use to construct that?

Warm regards,
JS

Loading Coils; was : Vincent antenna
 

John Smith wrote:
Dave Heil wrote:

...
Dave K8MN

Dave:

While your statements are quite well constructed to inflame and insult a
child--that has to do with your mind, not my age ... ROFLOL!

Which comments, "John"? You snipped everything I wrote.

Dave K8MN

Loading Coils; was : Vincent antenna
 

On 8 Dec, 07:56, Cecil Moore wrote:
Gene Fuller wrote:
Cecil Moore wrote:
Time permitting, I will work up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143

So how many nanoseconds does that 36.6 degree phase shift represent?

As far as impedance discontinuity *points* go, a nonsense
question.

How many nanoseconds does it take for a signal to travel
through a dimensionless point???? Well, let's see. What
is the speed of light multiplied by zero? Hmmmm, that's
a really tough one.

At any instant of time the forward voltage on
one side of the discontinuity *point* has a relative phase
difference from the forward voltage on the other side of
the *point*. This relative phase difference is constant as
long as the conditions remain unchanged.

The reason that it takes nanoseconds for a signal to travel
through a 75m Bugcatcher loading coil is that the coil is
NOT a dimensionless point. Mine occupies almost 200 cubic
inches. Loading coils with zero dimensions exist *only* in
the human mind and are impossible in reality.
--
73, Cecil http://www.w5dxp.com

Is "reality" confined to the speed of our brains or the
reflexes of our muscles or vision capabilities of our eyes?
To create is to produce to take the place of "nothing"
Your quest of TOTAL victory has reduced you to tunnel vision
Art

Loading Coils; was : Vincent antenna
 

Dave Heil wrote:

...
Which comments, "John"? You snipped everything I wrote.

Dave K8MN

That would be impossible for me to do; Look at your post, which "that
post" of mine responded to, all of your text is still there ...

JS

Loading Coils; was : Vincent antenna
 

John Smith wrote:
Cecil Moore wrote:
http://www.w5dxp.com/coiltest.gif

Beautiful artwork! What'd you use to construct that?

EZNEC and Paint.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

art wrote:
Your quest of TOTAL victory has reduced you to tunnel vision

Please don't confuse my not choosing to spend 36
hours a day defending the models I use with the
validity of the model. The lumped circuit model
is known to fail in distributed network configurations.
The distributed network model is known to work for
both lumped circuits and distributed network problems.
I am simply using the distributed network model.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Ian White GM3SEK wrote:
Your model can be as elaborate as you like, but
it always has to prove itself against the simple cases that we already
know about.

Since I am using the distributed network model proven
valid since before I was born, I don't have to defend
it. Please don't confuse my refusal to spend 36 hours
a day defending the distributed network model with the
validity of the distributed network model.

Likewise there are no glitches in the standard circuit models for
inductance and capacitance.

Really???? Just try your lumped inductance model on
a helical antenna and get back to us.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
Ian White GM3SEK wrote:
That is also the sensible way to think about loaded antennas.
Calculate it the simple way first, assuming lumped inductive loading,
and then apply corrections as necessary. As I've said before, this
simple, solid method is the one that works. It can take you straight
to a workable prototype, which can be quickly adjusted to frequency.
Countless authors have demonstrated how to do this, and anyone can
download G4FGQ's MIDLOAD program to do the same.

The point is that IT OBVIOUSLY DOESN'T WORK, Ian, for
the delay through a loading coil. If it worked, W8JI
would not have gotten a 3 ns delay through a 2" dia,
100 TPI, 10" long loading coil. If his test setup
looked like mine, he would have measured a valid
delay around 25 ns.

http://www.w5dxp.com/coiltest.gif

Ian, are you afraid to run that test for yourself?

Cecil insists that simple routine reality tests are a "diversion".

Please don't twist my words. I insist that simple routine
*UNreality* tests are a diversion. But, my personal opinion
doesn't change anything. The model that I am using works. The
model that W8JI is using doesn't work.

Please take a look at: http://www.w5dxp.com/coil512.ez
and tell me why EZNEC disagrees with W8JI's model.

Cecil,

I believe you said you saw about a 7% shift between the two inputs to
your scope. If the 75 meter frequency was 4 MHz that shift would
correspond to a time delay of 17.5 ns. Not 3 ns, but not 25 ns either.
Is that just an estimate based on rounding to the nearest 25 ns?

This entire issue has become one of counting angels on pinheads, at
least from a numerical view. One angel more or less really doesn't matter.

73,
Gene
W4SZ

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
art wrote:
Your quest of TOTAL victory has reduced you to tunnel vision

Please don't confuse my not choosing to spend 36
hours a day defending the models I use with the
validity of the model. The lumped circuit model
is known to fail in distributed network configurations.
The distributed network model is known to work for
both lumped circuits and distributed network problems.
I am simply using the distributed network model.

Yes, but not using it very well, or you would have been
able to answer the math problem I posed to you.
73,
Tom Donaly, KA6RUH

Loading Coils; was : Vincent antenna
 

On Dec 8, 9:22 am, Cecil Moore wrote:
Keith Dysart wrote:
You should count your posts on (re)reflections at the
output terminals of amplifiers.

Conceptually, I know what has to happen based on the
principle of conservation of energy, i.e. all energy
is conserved. If the reflected wave energy is not
entering the source, it is being reflected at the
source. That is all I was saying during those posts.

Actually, you said much more than that, some of
which was quite wrong. And you are right, some
of the errors would be entirely consistent with not
understanding amplifiers. Especially the
superposition ones.
But then why not take the opportunity to learn?
Instead of arguing from a point which you now
claim was ignorance.

....Keith

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
Ian White GM3SEK wrote:
Your model can be as elaborate as you like, but it always has to
prove itself against the simple cases that we already know about.

Since I am using the distributed network model proven
valid since before I was born, I don't have to defend
it. Please don't confuse my refusal to spend 36 hours
a day defending the distributed network model with the
validity of the distributed network model.

Likewise there are no glitches in the standard circuit models for
inductance and capacitance.

Really???? Just try your lumped inductance model on
a helical antenna and get back to us.

Yet more stinking dishonest quoting from Cecil. What I ACTUALLY wrote
was:

"Likewise there are no glitches in the standard circuit models for
inductance and capacitance. They work just fine, for all cases where the
dimensions of the circuit are very small with respect to the wavelength,
so that distributed effects and radiation are negligible. Where those
assumptions are no longer accurate, we can extend the simple model to
include some corrections. But the most important point is, we always
know that we're building up from a solid foundation."

There's no debating with that man. I've made my technical points, and
I'm out.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

Loading Coils; was : Vincent antenna
 

Gene Fuller wrote:
I believe you said you saw about a 7% shift between the two inputs to
your scope.

I don't recall saying anything like that. I don't even
know what that means. 7% of what?
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Tom Donaly wrote:
Yes, but not using it very well, or you would have been
able to answer the math problem I posed to you.

I'm sorry, Tom, I didn't even read the math problem
you posed to me as I don't have time for it right
now. I'm sure anyone could use the distributed
network model to solve your problem, even you.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Keith Dysart wrote:
But then why not take the opportunity to learn?
Instead of arguing from a point which you now
claim was ignorance.

Sorry, I didn't do that. My only point was that
one could indeed track the energy in the amplifier
if one understand where the destructive interference
is vs where the constructive interference is. Every-
thing I said is based on the conservation of energy,
not on the design of the amplifier.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

Ian White GM3SEK wrote:
Cecil Moore wrote:
Ian White GM3SEK wrote:
Likewise there are no glitches in the standard circuit models for
inductance and capacitance.

Really???? Just try your lumped inductance model on
a helical antenna and get back to us.

Yet more stinking dishonest quoting from Cecil. What I ACTUALLY wrote was:

"Likewise there are no glitches in the standard circuit models for
inductance and capacitance.

Yep, that's exactly as I quoted it.
--
73, Cecil http://www.w5dxp.com

Loading Coils; was : Vincent antenna
 

On Dec 8, 3:15 pm, "AI4QJ" wrote:
"Gene Fuller" wrote in message

...





Cecil Moore wrote:

---43.4 deg 600 ohm line---+---10 deg 100 ohm line---open

The Smith Chart does make it clear what is happening.
Here is the math to go with it. The impedance at the
junction of the two lines is:

-j100*tan(90-10) = -j100*tan(80) = -j567 ohms
-j600*tan(43.4) = -j600*tan(43.4) = -j567 ohms

The phase shift at the junction of the two lines is:
80-43.4 = 36.6 degrees

Time permitting, I will work up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143

So how many nanoseconds does that 36.6 degree phase shift represent?

8-)

In this example, we have transmission lines, not an antenna or antenna coil.
The total phase shift is 90 degrees or 62.5 nsec.

Only with great stretching.

The 10 degree 100 ohm line contributes 6.94nsec,

Correct.

the 43 degree 600 ohm line contributes 29.86 nsec.

Correct.

But now think in the time domain for a bit.
29.86 nsec after the signal is first applied it reaches the
discontinuity. 29.86 nsec later the first reflection arrives
back at the start. 13.8 nsec later the first reflection from
the end of the 100 ohm section arrives back at the start.
It takes many more reflections of reflections before the
impedance at the input starts to look like a short.

Nowhere in here will you be able to find anything that
happens in 62.5 nsec.

This is quite unlike an actual physical 1/4WL stub
where the first reflection does arrive back in
2 * 62.5 nsec. And the impedance at the input
behaves like a short after exactly 125 nsec.

Of course the ultimate is an actual short, where
Cecil's 90 degrees happens immediately.

These 90 degrees that Cecil insists are "always"
present are quite difficult to locate.

....Keith

Loading Coils; was : Vincent antenna
 

John Smith wrote:
Dave Heil wrote:

...
Which comments, "John"? You snipped everything I wrote.

Dave K8MN

That would be impossible for me to do; Look at your post, which "that
post" of mine responded to, all of your text is still there ...

Are you agog in Google World, "John"? There is no way of telling which
of my posts you responded to. My material was not quoted.

Dave K8MN

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
Tom Donaly wrote:
Yes, but not using it very well, or you would have been
able to answer the math problem I posed to you.

I'm sorry, Tom, I didn't even read the math problem
you posed to me as I don't have time for it right
now. I'm sure anyone could use the distributed
network model to solve your problem, even you.

Never mind.
73,
Tom Donaly, KA6RUH

Loading Coils; was : Vincent antenna
 

Ian White GM3SEK wrote:
Cecil Moore wrote:
Ian White GM3SEK wrote:
Your model can be as elaborate as you like, but it always has to
prove itself against the simple cases that we already know about.

Since I am using the distributed network model proven
valid since before I was born, I don't have to defend
it. Please don't confuse my refusal to spend 36 hours
a day defending the distributed network model with the
validity of the distributed network model.

Likewise there are no glitches in the standard circuit models for
inductance and capacitance.

Really???? Just try your lumped inductance model on
a helical antenna and get back to us.

Yet more stinking dishonest quoting from Cecil. What I ACTUALLY wrote was:

"Likewise there are no glitches in the standard circuit models for
inductance and capacitance. They work just fine, for all cases where the
dimensions of the circuit are very small with respect to the wavelength,
so that distributed effects and radiation are negligible. Where those
assumptions are no longer accurate, we can extend the simple model to
include some corrections. But the most important point is, we always
know that we're building up from a solid foundation."

There's no debating with that man. I've made my technical points, and
I'm out.



That's why you shouldn't take him seriously. He's like a college
wrestler who bites.
73,
Tom Donaly, KA6RUH

Loading Coils; was : Vincent antenna
 

Tom Donaly wrote:
Ian White GM3SEK wrote:
. . .
There's no debating with that man. I've made my technical points, and
I'm out.



That's why you shouldn't take him seriously. He's like a college
wrestler who bites.
73,
Tom Donaly, KA6RUH

We gotta learn better than to get down in the mud to rassle with a pig.
You both get dirty, and the pig loves every minute of it.

Roy Lewallen, W7EL

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:
Gene Fuller wrote:
I believe you said you saw about a 7% shift between the two inputs to
your scope.

I don't recall saying anything like that. I don't even
know what that means. 7% of what?

Cecil,

Sorry, English is not my native language this month. I must have
misinterpreted the following message sent by you (11/30/2007, 3:35 pm).

****************

Jim Kelley wrote:
Cecil Moore wrote:

I measured a ~25 nS delay in a 75m bugcatcher coil.

What did you use to make that measurement? (I hope you don't say you
used a Bird Wattmeter.)

I've described it before. I used a dual-trace
100 MHz O-scope and estimated the phase angle
between the two traces at about 7% of a cycle.
That phase angle was certainly NOT ANYWHERE
NEAR the 4.5 degrees reported by W8JI.

W8JI measured a 4.5 degree phase shift in the
standing-wave current being used for the
measurement although virtually no phase
information exists in the standing-wave current
phase. W7EL made exactly the same mistake in
his measurements. No wonder the two agree.
--
73, Cecil http://www.w5dxp.com


****************

73,
Gene
W4SZ

Loading Coils; was : Vincent antenna
 

Cecil Moore wrote:

I've described it before. I used a dual-trace
100 MHz O-scope and estimated the phase angle
between the two traces at about 7% of a cycle.
That phase angle was certainly NOT ANYWHERE
NEAR the 4.5 degrees reported by W8JI.

W8JI measured a 4.5 degree phase shift in the
standing-wave current being used for the
measurement although virtually no phase
information exists in the standing-wave current
phase. W7EL made exactly the same mistake in
his measurements. No wonder the two agree.

*Chuckle* I made the "mistake" of measuring current, the definition of
which can be found in any elementary electrical circuits text. Contrary
to Cecil's objections, phase is a property of periodic steady state
current (as can also be discovered from reading a basic text), and
certainly can be measured. I measured it and so did Tom, but Cecil sure
doesn't seem to like the results. Cecil's and his scope are apparently
able to measure something else -- whatever it is, I'm afraid my scope
doesn't have the magical properties needed to measure it.

I did, however, do at least a couple of things which Cecil might have
overlooked. One is that I was careful to terminate each of the current
probes with a low-resistance low-reactance load to reduce the insertion
impedance to a very low value. Another is that I put both probes on the
same wire to verify that their outputs were in phase. These steps alone
might have broken the magic spell necessary to measure whatever
different kinds of current Cecil imagines.

Can anyone point me to any reference to "standing-wave current" in any
reputable text? As far as I can tell, it's something Cecil made up to
mean whatever is necessary at the moment to discount others'
measurements. It seems to be working quite well -- in the endless
discussions, he's trotted it out many times without anyone to my
recollection even asking him what it is and how it differs from the
current described in textbooks (you know, the rate of charge flow?). Or
why "virtually no phase information" exists in it. A periodic waveform
with no phase information? Huh?

There's no mystery about traveling or standing waves -- both are very
well understood, mathematically rigorous, and have been used for over a
century with great success in the design of countless real things that
work. But muddled "standing wave currents" and bouncing waves of average
power, supported only by hand waving and misdirection, don't bear much
resemblance to the highly developed, rigorous, and self-consistent body
of knowledge that's served us so well for so long.

But each to his own.

Roy Lewallen, W7EL