Cecil Moore wrote:
"We have found that this expression gives acceptable results (errors
less than 10%) for most practical applications that involve wave
propagation on helical resonators ..." Absolutely no mention of
14WL self-resonance.

Gene Fuller wrote:
Oh darn! There's that nasty reference to "resonator" again. You really
need to read the paper again and attempt to understand it.

Try the left-hand column on the page for the fundamental mathematical
limitation that underlies everything else on the page, including Figure 1.

Since this is a question of literacy and not technology there is little
more to be said here.

Gene,

I can't believe you are still trying to get Cecil to actually read the
paper he is misquoting.
I've seen his debating style before. It's the last man standing wins,
no matter how obviously wrong he is. You'll never win that kind of
debate with logic or science Gene.

Never.

73 Tom

Gene Fuller wrote:
Oh darn! There's that nasty reference to "resonator" again. You really
need to read the paper again and attempt to understand it.

Uhhhhh Gene, a 75m bugcatcher coil is a "resonator" that
resonates an 8 foot mobile antenna on 75m. Take a look at
Figure 2 in Dr. Corum's paper. It looks just like a top-
loaded 160m mobile antenna.

Try the left-hand column on the page for the fundamental mathematical
limitation that underlies everything else on the page, including Figure 1.

There is a test equation to see if a particular coil is
outside the fundamental mathematicdal limitations. A 75m
bugcatcher coil is less than half the limit value.

Let me show you how to use Fig. 1. The coil that we have
been discussing is 6 inches in diameter and has 4 turns
per inch. That makes D/lamda = 2.0 x 10^3. That's just
about in the middle of the graphic. The turns per wavelength
is 48*246 = 11,808. That's just to the left of the left
hand curve. Reading the velocity factor from the graph
gives about 0.03 for that coil. It's a piece of cake
if you understand the physics involved.
--
73, Cecil http://www.qsl.net/w5dxp

wrote:
I can't believe you are still trying to get Cecil to actually read the
paper he is misquoting.

Unfortunately for your lumped circuit religion, I am not
misquoting anything. Page 4 contains a test to see if a
coil falls within the limitations of the velocity factor
equation. A 75m bugcatcher coil is less than half the
upper limit.

Here's the calculation: 5*N*D^2/lamda 1

N is turns per unit length and D is the diameter.

5*48*0.5^2/246 = 0.24 1

Therefore, the graph in Fig. 1 is valid for
75m bugcatcher coils and the velocity factor is around
0.02. The VF equation yields the same value as the graph.

The lumped circuit model is known to fail. Dr. Corum knows
where it fails. Most people on this newsgroup don't know.
And when it does fail, the distributed network model gives
valid results.

Why would you ever choose a model known to fail without
knowing where it fails when you could be using a model known
to be valid?
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
wrote:

I can't believe you are still trying to get Cecil to actually read the
paper he is misquoting.


Unfortunately for your lumped circuit religion, I am not
misquoting anything. Page 4 contains a test to see if a
coil falls within the limitations of the velocity factor
equation. A 75m bugcatcher coil is less than half the
upper limit.

Here's the calculation: 5*N*D^2/lamda 1

N is turns per unit length and D is the diameter.

Cecil,

Selective quoting can have the same effect as misquoting. If one goes
back a few words in the same long sentence it can be observed that the
more complete limitation is stated as:

"... an approximation for M has been determined by Kandoian and Sichak
which is *appropriate for quarter-wave resonance* and is valid for
helices with 5*N*D^2/lambda 1 ..."

[emphasis was in the original]

You apparently choose to accept the second half of the condition while
ignoring the first half. In most cases the "AND" construction means both
parts apply.

Do you really think the Vf is dependent only on the turn density and not
the number of turns? Corum never says such a thing, since the number of
turns is dictated by the resonance requirement. How far down does your
magic extend? To half the turns needed for resonance? To one turn? To
less than one turn? Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?

For anyone still reading who is bored (everyone) or confused by this
topic (perhaps) the importance to the subject at hand is that Cecil has
mis-used this reference paper to "prove" that the 75 meter loading coil
replaces approximately 45 degrees of the original unloaded quarter wave
antenna. After his long struggle to prove his point with modeling, and
achieving only 10 degrees of phase replacement, he abandoned that
approach for this latest futile attempt. The "missing" portion of the
test antenna is about 75 degrees, so 45 degrees would barely squeak in
under the 59% precision rule.

73,
Gene
W4SZ

"Gene Fuller" wrote:
Selective quoting can have the same effect as misquoting. If one goes
back a few words in the same long sentence it can be observed that the
more complete limitation is stated as:

"... an approximation for M has been determined by Kandoian and Sichak
which is *appropriate for quarter-wave resonance* and is valid for
helices with 5*N*D^2/lambda 1 ..."

I have already explained that to you twice now, Gene. This is the third
time so listen up. They were looking for a formula "appropriate for
quarter-wave resonance" and they found one that works for lengths
other than a quarter-wavelength. If it worked *only* for quarter-wave
resonance, they would have said so. You are confusing a mutually
inclusive statement with a mutually exclusive statement.

Do you really think the Vf is dependent only on the turn density and not
the number of turns? Corum never says such a thing, ...

Already asked and answered. He certainly does imply such a thing in Fig. 1.
The VF is dependent only on the turn density and the diameter of the coil.
The number of turns affects the length of the coil. The length of the coil
is NOT a parameter in the graphic nor does it appear in the equation.

Does a 1/4WL transmission line have a different VF when it is increased
to 1/2WL?

Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?

Already asked and answered. If you cannot read Fig 1, then you have
a problem. The VF in the graphic goes from 0.0 to 1.0.

After his long struggle to prove his point with modeling, and
achieving only 10 degrees of phase replacement, he abandoned that
approach for this latest futile attempt.

The voltage was 67 degrees out of phase with the current so we weren't
dealing with traveling waves. That's why I abandoned it - because I was
on the verge of making the same mistake that W7EL and W8JI already
made - trusting measurements in the presence of standing waves.

The "missing" portion of the
test antenna is about 75 degrees, so 45 degrees would barely squeak in
under the 59% precision rule.

Once again, there is no "missing" portion of an antenna. The delay through
the loading coil is what it is. There is absolutely no requirement that it
be
a certain number of degrees.

What is required is that (Vfor+Vref)/(Ifor+Iref) be purely resistive at the
feedpoint. There is absolutely no requirement for the antenna to be 90
degrees long. That is just another one of your many strawmen.

I am trying to zero in on the technical facts. What are you trying to do?
--
73, Cecil, W5DXP

"Gene Fuller" wrote in message:
Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?

Take the VF=0.02 resonant coil and divide it into two equal
coils. Do you really expect the two coils to have VFs of 1.0
while their end-to-end combination results in a VF of
0.02? Please quote the laws of physics that allows such
to happen.
--
73, Cecil, W5DXP

Cecil Moore wrote:
"Gene Fuller" wrote:


Do you really think the Vf is dependent only on the turn density and not
the number of turns? Corum never says such a thing, ...


Already asked and answered. He certainly does imply such a thing in Fig. 1.
The VF is dependent only on the turn density and the diameter of the coil.
The number of turns affects the length of the coil. The length of the coil
is NOT a parameter in the graphic nor does it appear in the equation.

Does a 1/4WL transmission line have a different VF when it is increased
to 1/2WL?


Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?


Already asked and answered. If you cannot read Fig 1, then you have
a problem. The VF in the graphic goes from 0.0 to 1.0.


Cecil,

You just contradicted yourself. Yes, indeed, Fig.1 shows Vf going from
0.0 to 1.0. But as you pointed out, there is no dependency on the number
of turns anywhere in the chart axes or in the plotted data. It would be
useful if you looked at the caption on that figure to attempt to
understand what is actually being plotted. The vertical scale is Vf and
the horizontal scale is D/lambda. The parameter attached to each curve
is "N", which is defined as the turns per wavelength.

We would expect a very short coil to look like a straight wire, with a
Vf near 1.0. How does the Vf transition to 0.02 for a resonant coil
occur? That transition is most certainly NOT shown in Fig. 1.

73,
Gene
W4SZ

On Thu, 20 Apr 2006 15:01:57 GMT, Gene Fuller
wrote:
For anyone still reading who is bored

Hi Gene,

To ask about those still reading, there is one very good reason why
the thread persists: topic drift as your post has just raised the
opportunity to:
1. argue the original quotation by shifting authors;
2. argue the subquotation in terms of ANDing where his sum of the
parts never equal the whole;
3. respond to "do you think the Vf" in terms that diverge from your
yes/no;
4. argue no one uses a one turn coil load for 160M (this is all
getting too easy to dissemble);
5. discuss transitions when you obviously don't believe they exist
(more arguments over inconsequentials);
6. counter-claim old claims (aka correcting what he would call your
bad context);
7. argue models (he has already questioned EZNEC's capacity in some
form - you will only tread that old ground once again);
8. fight over "missing" portions of the antenna - Cecil can prove he
never "exactly" said it did!;
9. ... and more through finer parsing than found here (and it is
guaranteed to be found, that has been amply demonstrated when you feed
the troll).

Those exchanges are like watching someone chase the clown in a
revolving door with discarded lines of attack flying out like grass
clippings from a lawn mower.

Cecil has never been able to hold his ground to one point when I've
drilled down instead of following the outrageous. No one want to
abandon the only true content, the comedy; but, really, the knots of
argument are far more deterministic than the technical issue
supposedly being discussed.

73's
Richard Clark, KB7QHC

Cecil Moore wrote:
"Gene Fuller" wrote in message:

Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?


Take the VF=0.02 resonant coil and divide it into two equal
coils. Do you really expect the two coils to have VFs of 1.0
while their end-to-end combination results in a VF of
0.02? Please quote the laws of physics that allows such
to happen.
--
73, Cecil, W5DXP


Cecil,

What is the mystery? Have you never seen a response curve for a resonant
condition? It is not exactly linear.

You are the expert on Vf. You assert without proof that a half-length
coil has the same Vf as the full-length resonant coil. OK, even if I
accepted that supposition, what happens at a quarter-length or at a
tenth-length? I am simply asking how the function changes between the
"known" limits of 1.0 and 0.02. You have repeatedly ducked any sort of
answer.

73,
Gene
W4SZ

"Gene Fuller" wrote:
We would expect a very short coil to look like a straight wire, ...

There you go again. We are not talking about very short coils.
We are talking about big honking 75m bugcatcher coils. We
are talking about taking a 1/4WL self-resonant coil and cutting
it into two equal sized coils. The VF is not likely to change by
more than 10%.

How does the Vf transition to 0.02 for a resonant coil
occur? That transition is most certainly NOT shown in Fig. 1.

Of course it is shown. Draw a vertical line at 10^-3. The 10k
turns per lamda coil has a VF of 0.07. The 50 turns per lamda
has a VF of 0.86. Exactly the same principle applies to your
question.
--
73, Cecil, W5DXP