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Old November 6th 03, 04:26 PM
Cecil Moore
 
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Ian White, G3SEK wrote:

Cecil Moore wrote:
Ian, I apologize if my humor offended you.


It wasn't the "humor" (which was too feeble to offend anyone) but your
talent for turning any technical discussion into a total waste of time.


Imaginary circuits impossible to achieve in reality are not a waste of
time? What is the agenda for diverting the discussion away from reality
to something that cannot possibly exist in reality? I may be wrong, but
it seems to me that agenda simply seeks to avoid the truths that will be
uncovered by limiting the discussion to things that are possible.

Since lumped inductors are impossible to achieve in reality, one might
assert that they can sit up and spit cider in your eye. (From an old
Dean Martin movie) How could you ever prove otherwise since the
assertion cannot be tested?
--
73, Cecil http://www.qsl.net/w5dxp



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  #232   Report Post  
Old November 6th 03, 04:36 PM
Cecil Moore
 
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Richard Harrison wrote:

Cecil, W5DXP wrote:
"Until someone can explain exactly how a lumped inductor causes a
45-degree phase shift in the current, I`m going to assume that a lumped
inductor is incapable of that feat."

There are base loading coils in shielded boxes which don`t radiate but
do have significant inductance which make too-short antennas seem long
enough for impedance matching purposes.


But the point is, those loading coils in shielded boxes are NOT *lumped
inductors*. We have been told that lumped inductors have zero phase shift.
Apparently, a 45-degree phase shift in the current through a lumped inductor
would violate the rules of usage for lumped inductors.

I have no doubt that real-world inductors provide a phase shift in the
current. My statement was limited entirely to lumped inductors, a purely
imaginary conceptual model. Sorry if that wasn't clear.
--
73, Cecil http://www.qsl.net/w5dxp



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  #233   Report Post  
Old November 6th 03, 04:52 PM
Yuri Blanarovich
 
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KB7QHC wirtes:
As this is your party, the burden of proof is upon you. I supplied
you with a litany of trip-points and you in fact responded to none.


I appreciate your points, some are valid, I know about them, some were off
target, some are in the area of nitpicking, when we are overlooking bigger
picture.

I explained that your previous posting was based on wrong assumptions (not
reading carefully the threads?) - the 100mA on 8A meter, measurement
techniques, etc.

I will do my tests and measurements, first I will do that on my Radiomobile, to
test the real life typical mobile situation. Next it would be to replicate
W9UCW setup with radials.

I keep getting "arguments" that are nitpicking in the .01 area of significance
vs. 50% and the facts.

I presented 7 points of proof and asked if anyone can debunk them, prove wrong,
so far not a single "overthrow".

Let me try to summarize again briefly:

The temperature test, feeling or thermal strips prove that there is not .1
difference in current accross the loading coil but around 50%.

W9UCW measured it and showed 40 - 60% differences.

W5DXO explained mechanics of the effect.

Are the FACTS in the way of coil "must" have the same current theory?

This is not enough proof that current is significantly different at both ends
of the coil rather than miniscule, hardly measureable? That IS the argument.

As has been demonstrated, there is a camp that believes the current is the
same. We know it is not and are bringing it to their attention in hope that it
will set the record and knowledge straight. If they choose not to believe it,
then let them be happy with their calculated world.

Anyone measured it yet?

Yuri, K3BU.us

  #234   Report Post  
Old November 6th 03, 06:00 PM
Cecil Moore
 
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Yuri Blanarovich wrote:
Are the FACTS in the way of coil "must" have the same current theory?

This is not enough proof that current is significantly different at both ends
of the coil rather than miniscule, hardly measureable? That IS the argument.

As has been demonstrated, there is a camp that believes the current is the
same. We know it is not and are bringing it to their attention in hope that it
will set the record and knowledge straight.


One more data point. Assuming a 102 inch base-loaded mobile antenna on 75m,
the impedance looking into the whip is around 0.5-j2000. If we assume a current
of 1.5 amp into the bottom of the coil and also out of the top of the coil,
the voltage at the top of the coil will be around 3000 volts.

With a base loaded 75m antenna, the voltage at the top of the coil should
not be extremely difficult to measure and could be viewed with an oscilloscope.
This is an experiment that I can do at reduced power.
--
73, Cecil http://www.qsl.net/w5dxp



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  #235   Report Post  
Old November 6th 03, 06:13 PM
Jim Kelley
 
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Cecil Moore wrote:
We have been told that lumped inductors have zero phase shift.


I think the claim is that there is zero current differential in
magnitude across a lumped inductor. It's certainly true of a pure
inductor. Presumably, one in which radiation is not a factor, and for
which the electrical length is short compared to wavelength.

73, Jim AC6XG


  #236   Report Post  
Old November 6th 03, 06:16 PM
Richard Harrison
 
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Cecil, W5DXP wrote:
"My statement was limited entirely to lumped inductors, a purely
imaginary conceptual model."

Sorry I didn`t get the picture. An inductor that provides no phase shift
is similar to a capacitor that holds no charge. Inductors and capacitors
store energies in their magnetic and electric fields. Current lags in
the inductor and leads in the capacitor. Pure reactances have a
90-degree phase shift between applied voltage and resulting current by
definition.

An inductor sans phase shift is salt without savor or sugar without
sweetness.

Lumped inductance means coiled in place of straight wire, to me.
Reference to toroidal coils in this thread implied to me an absence of
external field, for which I chose a shielded coil with a straight-axis
for my example.

I agree with Cecil that a 90-degree antenna which includes only a
45-degree length of wire needs another 45-degree phase-shift in its
length to reach the full 90-degrees.

As the coil is in series with a resistance, and the resistance the coil
experiences depends upon its position between drivepoint
(low-resistance) and far end (high resistance) at the end of the
element, the inductance required to produce the same required phase
shift, varies with its position in the element.

Where the resistance is low, so is the required inductance. Where the
resistance is high, so is the required inductance, and it is all for the
same number of degrees that the antenna is short.

Best regards, Richard Harrison, KB5WZI

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Old November 6th 03, 06:36 PM
Jim Kelley
 
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Cecil Moore wrote:
If a loading coil has no effect on the current or the electrical
length of the antenna, exactly what effect does it have?


Apparently the correct answer is "loading".

73, Jim AC6XG
  #238   Report Post  
Old November 6th 03, 07:00 PM
Richard Clark
 
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On 06 Nov 2003 15:52:29 GMT, oSaddam (Yuri Blanarovich)
wrote:
I explained that your previous posting was based on wrong assumptions (not
reading carefully the threads?) - the 100mA on 8A meter, measurement
techniques, etc.


Hi Yuri,

This, above, is exactly my complaint and it illustrates how you are
projecting your problem on me. It is you who is not reading carefully
because you did not respond to the issues, but rather injected this
specious comment.

I responded specifically to 100mA, I responded specifically to 8A, I
responded to how you are going to lose accuracy through scaling, I
responded specifically to how you could approach that, I responded
directly to what it would demand. You answered NONE of these
technical issues and instead made this lame complaint above. You left
me to speculate about the model - NO RESPONSE to that either. You
left me to speculate about drive level - NO RESPONSE to that either.
You describe the enormous heat issues that come with these
characteristics that have been UNRESPONDED to. Instead you dismiss
the issue of heat in the same breath as applied to a caloric based
measuring device as:
nitpicking in the .01 area of significance

Which is unsupported by any data. Obviously you find it simpler to
reject than to investigate. This is the class of argument you decry
coming from Tom, but it is consistent with the class of sneer review
common in this forum.

As I stated, please insert the stage directions [applause here] for
your scripting if you are not going to respond to the technical
comments.

What is the program? If you prefer (as shown by your more than single
participation in) these ethereal speculations of how to measure a real
infinitesimal component (a contradiction on the face of it); then
please for the sake of truth in labeling also mark your postings as
being "for entertainment only."

73's
Richard Clark, KB7QHC
  #239   Report Post  
Old November 6th 03, 07:14 PM
Richard Harrison
 
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Yuri, K3BU wrote:
"Are the FACTS in the way of coil "must" have the same current theory?"

Sure. Power traveling along a radiator is absorbed in resistance, both
loss and radiation resistance, so it is diminished by the time it gets
to a reflection point, the tip of the antenna. This is not like a coil
without an opportunity to radiate or which is small in terms of
wavelength.

Often an extreme example is more impressive than the mediocre. For
instance, complete reflections on a lossless line make clearer examples
of phase patterns than slight mismatches on a lossy line.

For a coil, use the example of the "normal helix antenna". At one of the
radio broadcast stations where I worked in 1949, was an operator, James
L. Davis, W5LIT who wrapped a bamboo fishing pole completely from end to
end with wire in the form af a solenoid, using it as his rear bumper
mounted 75-meter phone mobile antenna. When he modulated, the corona at
its tip echoed his voice.

Obviously, there was a huge difference in the drivepoint current (high)
of this antenna, a continuous coil, and the current at the tip (low).
The voltage was the reverse of its end currents, being high where the
current was low and being low where the current was high. J.L. Davis was
very pleased with his mobile operation.

Best regards, Richard Harrison, KB5WZI

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Old November 6th 03, 07:53 PM
Cecil Moore
 
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Jim Kelley wrote:

Cecil Moore wrote:
We have been told that lumped inductors have zero phase shift.


I think the claim is that there is zero current differential in
magnitude across a lumped inductor. It's certainly true of a pure
inductor. Presumably, one in which radiation is not a factor, and for
which the electrical length is short compared to wavelength.


For a lumped inductance, the electrical length is zero. Presumably,
that has a zero effect on the current. Assuming that only the voltage
is affected, the phase relationship between the voltage and current
is blown compared to an unloaded antenna. But the relationship is
somehow (magically?) restored by the time the end of the antenna is
encountered. Exactly how is that relationship restored?
--
73, Cecil http://www.qsl.net/w5dxp



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