wrote:

Cecil Moore wrote:
Time to stop the ad hominem attacks and address this technical issue.

When you show a track record of being honest and you stop those attacks
and your constant distortions of what other people say, I'm sure people
will start talking to you again.

So by demonizing me, you avoid any technical discussion that
might prove you wrong. That's pretty transparently obvious, Tom.
--
73, Cecil http://www.qsl.net/w5dxp

Tom Donaly wrote:
Here's a more general equation for you Cecil:
(A1-A2)*Cos(wt-kx) + 2*A2*Cos(kx+d/2)*Cos(wt+d/2).

Yes, it is more general, Tom, but since the subject is standing
waves and not traveling waves, it is overly general. Why would
you post an equation containing a traveling wave term when the
subject is the equation for standing waves?

This is the total equation for the condition where power is
being delivered to a load in the presence of standing waves.
The first term makes it to the load. The second term doesn't.

The first term is a traveling wave and indeed does contain
phase information. There's no argument about whether a
traveling wave contains phase information.

The argument is whether the second term, the standing wave
term, contains phase information. Gene Fuller says it doesn't,
Eugene Hecht says it doesn't, and I'm inclined to agree.
--
73, Cecil http://www.qsl.net/w5dxp

wrote:
When you show a track record of being honest and you stop those attacks
and your constant distortions of what other people say, I'm sure people
will start talking to you again.

Of course, you never attack anyone. Pot, Kettle - Kettle, Pot. Here's
a smattering of what you have said to me during the past month:

W8JI wrote:

3/5/06 "Cecil, You are a horse's ass."

3/10/06 "If you weren't so pig-headed ... Until you stop, put the beer away,..."

3/11/06 "I'm also a victim of Cecil's twicted reality now."

3/11/06 "It would be comical to watch Cecil twist reality if it wasn't sad."

3/11/06 "Cecil's normal tactic is to change what other people say."

3/27/06 "how much will you pay me for putting up with you?"

3/27/06 "I feel sorry for anyone who has to deal with you on a daily basis.
No wonder your wife split."
--
73, Cecil http://www.qsl.net/w5dxp

Richard Fry wrote:
But clearly these lengths in degrees do not define the self-resonant
length of that radiator.

Could it be that the resonant 80 degrees of physical length
is 90 degrees of electrical length?
--
73, Cecil http://www.qsl.net/w5dxp

wrote in message
ups.com...
but we can not
use electrical degrees to 'splain the behavior of coiled antenna wire?

I can see how problems could arise going by the length of coil
wire length in degrees only. Lets say you run a coil 1 foot from the
base. Lets say that coil uses 25 turns to tune a particular frequency.
Now, move the coil up 2 ft higher, and see if that same 25 turns will
tune the same frequency. It won't. You will have to add a few more
turns.
So just going by the total mast plus coil wire length in degrees could
vary
all over the map just by changing the position of the coil. As you
raise
the coil, you will have to add more and more of "degrees" of wire to
tune the same frequency. :/
Dunno...There may well be some variation of current from the bottom
vs the top of the coil, but overall, I still view the operation of a
loading
coil as a "lumped" mechanism overall.
Even if you all decide that the current changes, or it doesn't , it
ain't
gonna make a hoot's worth of difference in the design of mobile whips.
I think it's an argument that has no real value to me as far as mobile
whips go. The performance of all the various coil heights, and configs
have been well known for years. Coil current taper or not.
I just don't see the facination with arguing about something that even
if
decided one way or the other, still won't make any difference in the
final
antenna design. Oh well...Continue the tail chasing excercise....
I'm outa this one... One post is all I will waste on this subject..
I couldn't mount my coil much higher if I wanted to... Current taper or
not. :/
MK


MK, that is the whole point, that you portray missing or not appreciating.
It might not matter to you if you lose $100, but it might matter to someone
else. Same with loading coil. What you are describing, the effect where the
coil is located, being known, is the result of the phenomena we are trying
to straighten out, explain and apply properly in modeling and design
exercises.

The position of coil within the antenna has significant effect. The worst is
at the base, fewer turns required. The best is somewhere about 2/3 up the
radiator, more turns required. You stick it on the top, no stinger or hat,
you get it almost invisible. With what we are discussing and defending here
is the proper understanding of the current flow in the loading coil and its
drop across and its effect on the efficiency of the loaded antenna.
Efficiency is proportional to the area under the current curve distribution
along the radiator. If you properly model the coil as solenoid or loading
stub to see the real drop of current across the coil and its effect in
various positions along the radiator, the all is clear and is with agreement
with practical experience, antenna shootout results, measurements.
As I mentioned numerous times, its effect on design and modeling loaded
antenna systems will be even more pronounced, because effect gets magnified
when you start adding elements. This is especially important when you try to
design super receiving antennas for low bands where F/B and clean pattern is
very desirable and is the most critical aspect of antenna design or
modeling. It is harder to obtain the max F/B or least rear lobes than to
maximize the design for max gain.
It might not matter to you, but I am sure many would benefit from knowing
more precisely what is REALLY going on and then use or correct their design
methodology.
I think it is fine for you to ignore this and poh-poh it. But I know how
huge difference it made in my 160m mobile antenna when I extended the whip
to the front bumper with wire.
We are not saying that piece of wire that coil is wound with, has so many
electrical degrees. If we carefully consider and understand the phenomena,
you would realize that the radiator has same electrical length (say 15 deg)
and when you move the coil and ADJUST THE TURNS to bring the antenna back to
resonance (90 deg) that coil would "replace, take care of" 75 degrees. The
turns have to be adjusted in order to "participate" in the current
replacement game. The lesson is, the higher you place the coil on the
radiator, the more turns you need to reresonate the radiator, the high
current portion of the antenna current distribution curve gets "stretched
up", better efficiency (larger area under the overall curve). Then the coil
DROPS the current across itself to some lower value, which then continues to
drop across the tip and that area, quite smaller adds to the one from the
bottom part of the radiator.
This all is supported by reality, except "gurus" who insist that the current
is (about) the same across the coil and they make (theoretically) antenna
current to be higher across the tip and "more" efficient than it is. Again,
you stick 6 of those in the 3 el loaded Yagi design and you get GI-GO.

It is known how profound effect had replacement of loading stubs by coils in
the KLM 3 el. 80 m loaded Yagi. Better gain, huge improvement in the F/B and
pattern. Has been done and described. And this is just replacing the same
inductance value stub with coil, where delta current from stub wires was
enough to throw monkey wrench in the Yagi performance. Now consider larger
error from the wrong assumption or calculation caused by wrong current
magnitudes and distribution.

Again you might not give a hoot about this "trivial" exercise, but if I want
to design 4 el loaded quad or Yagi for 80 or 160, it matters a lot.
So it just amazes me that some of the smarter heads resist so much in trying
to find out reality and develop better consideration of the effect for
design and modeling. No technical answers to Cecil's questions and my "from
scratch" thread deteriorated into pink electrons and dead end in electrical
degrees.

So far what we have is the reality, few who are trying to legitimize it and
few who got off on the wrong foot, in effort to preserve their (wrong) face
they cling to it with scientwific "proofs" why it can't be so, when IT IS.
When I tried to go step by technical step through the case, the "gurus" are
not there. Cases that Cecil showed in EZNEC model and demonstrating that
current across the loading coil (not one in the box) in the antenna can have
anything from equal to "nothing" at the other end, depending on its position
in the standing wave picture. It all jives with our original argument. We
spotted the "problem", we dissected it, thanks to fierce flat earthers, and
now have better understanding of the phenomena and can use to design better
antennas.
I care about antennas, this is the last frontier where we can still improve
thing, now with modeling tools. I still operate contests and go for
ultimate - beating the all time records, and that's where the edge can be
obtained.

Heloooo guys!
Measure, feel, whatever, the frickin' current across the loading coil and
then come back and tell the world why it IS different, but IT CAN'T be so,
because you said so in the beginning and you just can't admit being wrong.
Reality can't be twisted, just like Earth is not going back to flat!
Saying now that is no big deal, not important, will not exonerate the
"wrongoes". It is significant not to be ignored. If I was in "their" shoes,
I would say: "gee guys, interesting, thanks for bringing it up, explaining
it, I guess we were wrong, now we can design better antennas". Stay
tuned.....

Thanks again Cecil, Richard and others for putting up with and shedding more
and more light on the phenomena. It must go down in history as big as
Galileo's fight :-) I am glad that, hopefully, nobody will burn us.

73 Yuri, K3BU.us

On Tue, 4 Apr 2006 10:32:08 -0400, "Yuri Blanarovich"
wrote:

Now consider larger
error from the wrong assumption or calculation caused by wrong current
magnitudes and distribution.

Hi Yuri,

Why is it that you can say this so often, and yet never put a number
to it?

What is the error? You also speak of efficiency. What is the
efficiency?

Very simple questions. Technically based. Selected because they seem
to be of supreme importance to you, and yet you don't seem to have a
handle on the situation.

73's
Richard Clark, KB7QHC

"Cecil Moore" wrote ...
Richard Fry wrote:
But clearly these lengths in degrees do not define the self-resonant
length of that radiator.

Could it be that the resonant 80 degrees of physical length
is 90 degrees of electrical length?
__________

That a self-resonant, unloaded broadcast radiator length is shorter than the
90 degree conventional "electrical length" defined by the FCC is a given.
But this reality sometimes is not recognized.

RF

Cecil Moore wrote:
John Popelish wrote:

Cecil Moore wrote:

Compared to zero amps of standing wave current when the forward current
phasor and the reflected current phasor are 180 degrees out of phase,
just how much effect can capacitance have?


A standing wave voltage passes exactly as much (AC RMS) current
through a capacitance as a traveling wave voltage does.


But the two waves are different as can be seen from their
equations.

That difference is a difference in the pattern (distribution) of
voltage and current along the line, as well as a possible difference
in amplitude and phase at any given point. But at any point that is
not a node in the standing wave pattern, there will be an ordinary AC
voltage or current at some amplitude between double the traveling wave
amplitude and zero amplitude, and one of two phases (that switch each
time you pass a node).

A traveling wave transfers net energy along a
transmission line or antenna wire. A standing wave transfers
zero net energy along a transmission line or antenna wire.

No argument. But a standing wave still represents storage of energy
in the line, as with any resonant structure, and that stored energy
shows up as magnetic fields and electric fields along the line. The
big difference is that the magnetic fields bob up and down at some
areas and the electric fields bob up and down half way in between
those areas. At any given moment, there is a fixed total energy in
the combination of all the magnetic and electric fields.

In the areas where the electric field is bobbing up and down, there
must be capacitive current caused by that variation in electric field.

From "Fields and Waves in Modern Radio", by Ramo & Whinnery,
2nd edition, page 43: "The total energy in any length of line
a multiple of a quarterwavelength long is constant, merely
interchanging between energy in the electric field of the
voltages and energy in the magnetic field of the currents."

Exactly. How can you write this, but deny the capacitive current that
delivers this electric field energy twice every cycle to all
capacitance feeling this voltage swing?

Hecht says it best in "Optics" concerning standing waves:

"The composite disturbance is then:

E = Eo[sin(kx+wt) + sin(kx-wt)]

Applying the identity:

sin A + sin B = 2 sin 1/2(A+B)*cos 1/2(A-B)

yields:

E(x,t) = 2*Eo*sin(kx)*cos(wt)"

cos(wt) is the AC swing that drives the capacitive current. sin(kx)
is the positional variation of that AC voltage along the line. I have
absolutely no argument with the expression, only with your
understanding of what it says.

"This is the equation for a STANDING or STATIONARY WAVE, as opposed
to a traveling wave. Its profile does not move through space; it is
clearly not of the form Func(x +/- vt)."

Profiles do not charge capacitance, instantaneous rate of change of
voltage drives current through capacitance. cos(wt) describes a
sinusoidal variation of voltage over time (you couldn't have an RMS
value of voltage at a point or an RMS value of current past a point,
without it.

[Standing wave phase] "doesn't rotate at all, and the resultant
wave it represents doesn't progress through space - its a standing
wave."

I suggest you drop talking about phasors, till you understand what
cos(wt).

Speaking of "... net transfer of energy, for the pure standing
wave there is none."

But it does represent net storage of energy. The total stored energy
is the sum of energies in the two traveling waves over the length. A
standing wave does not violate conservation of energy.

Storage that must continuously be swapping back and forth from
magnetic field energy to electric field energy. When the energy
storage is all electric, that implies charges capacitance.

Don't give up, the light may be just about to come on.

Cecil Moore wrote:
Tom Donaly wrote:

Here's a more general equation for you Cecil:
(A1-A2)*Cos(wt-kx) + 2*A2*Cos(kx+d/2)*Cos(wt+d/2).


Yes, it is more general, Tom, but since the subject is standing
waves and not traveling waves, it is overly general. Why would
you post an equation containing a traveling wave term when the
subject is the equation for standing waves?

This is the total equation for the condition where power is
being delivered to a load in the presence of standing waves.
The first term makes it to the load. The second term doesn't.

The first term is a traveling wave and indeed does contain
phase information. There's no argument about whether a
traveling wave contains phase information.

The argument is whether the second term, the standing wave
term, contains phase information. Gene Fuller says it doesn't,
Eugene Hecht says it doesn't, and I'm inclined to agree.

Cecil, I won't try to educate you because it's a waste of time, but
for everyone else, consider that in an antenna, there is
energy going into, and being radiated out of, the antenna in the
form of an electromagnetic wave. Since Cecil says standing waves
can't transfer energy from one place to another (he didn't always
say this) that means that the only way energy can be radiated is
through the traveling wave component of the electromagnetic wave.
You would think that this would be important to him in his search
for a dumbed down theory of reflection mechanics, but evidently
he is more interested in his arguing point concerning Tom R. and
Roy measuring current in a standing wave environment than he is in
reaching an understanding of what he's talking about. No wonder
no one's communicating with him.
73,
Tom Donaly, KA6RUH

John Popelish wrote:
But at any point that is not a
node in the standing wave pattern, there will be an ordinary AC voltage
or current at some amplitude between double the traveling wave amplitude
and zero amplitude, and one of two phases (that switch each time you
pass a node).

Please give us the equation for "ordinary AC voltage or current".

No argument. But a standing wave still represents storage of energy in
the line, as with any resonant structure, and that stored energy shows
up as magnetic fields and electric fields along the line. The big
difference is that the magnetic fields bob up and down at some areas and
the electric fields bob up and down half way in between those areas. At
any given moment, there is a fixed total energy in the combination of
all the magnetic and electric fields.

No argument, and therefore no need for the "But" in your statement.
I agree with you but it doesn't change a thing about the real
argument.

Exactly. How can you write this, but deny the capacitive current that
delivers this electric field energy twice every cycle to all capacitance
feeling this voltage swing?

I don't deny it - never have - never will. Please stop trying
to set up straw men. The discussion has *NEVER* be about what
happens during one cycle. The current measured by W8JI and W7EL
and reported by EZNEC is RMS current. Instantaneous values are
just another straw man diversion.

Profiles do not charge capacitance, ...

I'm glad you agree. Profiles are maximum RMS envelope values
and that is what EZNEC reports.

[Standing wave phase] "doesn't rotate at all, and the resultant
wave it represents doesn't progress through space - its a standing
wave."

I suggest you drop talking about phasors, till you understand what cos(wt).

Hecht and I have been a little lose with words while assuming
the readers have a certain knowledge level. For the uninitiated,
When Hecht (or I) say the phasor doesn't rotate at all, we
mean the phasor doesn't rotate at all with respect to the
source phasor. Any initiated person would know that. The phase
of the standing waves doesn't change with respect to the phase
of the source signal. Hecht assumed you would know what he meant
by that statement.

Speaking of "... net transfer of energy, for the pure standing
wave there is none."

A standing wave does not violate conservation of energy.

Exactly my point! Nothing violates conservation of energy. If
the RMS forward current in the coil is the same magnitude at
both ends and the RMS reflected current in the coil is the
same at both ends, the conservation of energy principle is
satisfied NO MATTER WHAT THE STANDING WAVE CURRENT TURNS
OUT TO BE. What is it about that statement that you don't
understand?

Storage that must continuously be swapping back and forth from magnetic
field energy to electric field energy. When the energy storage is all
electric, that implies charges capacitance.

Again, nobody has ever been discussing what happens within a
partial cycle. Discussion of such is obviously a diversionary
straw man. Feel free to find someone else willing to discuss it.
It is completely irrelevant to this discussion of RMS envelope
values.
--
73, Cecil http://www.qsl.net/w5dxp