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

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

"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

On Thu, 20 Apr 2006 17:45:39 GMT, "Cecil Moore"
wrote:

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
That is for coil A
has a VF of 0.07.

The 50 turns per lamda
That is for coil B
has a VF of 0.86.
Well, in fact it does not (and nothing shown on the graph along that
ordinal line does).

Do we now hear the pity card played about poor eyesight? Or the pity
card played about poor computational skills (±59%)? Or the pity card
played for the confusion of old age when two coils are substituted in
the old shell game?

"Richard Clark" wrote:

w5dxp wrote:
Of course it is shown. Draw a vertical line at 10^-3.
The 10k turns per lamda coil
That is for coil A
has a VF of 0.07.

The 50 turns per lamda
That is for coil B
has a VF of 0.86.
Well, in fact it does not (and nothing shown on the graph along that
ordinal line does).

What happened should be obvious. I correctly used the 10^-3
vertical line for the first one and accidentally used the 0.01 vertical
line for the second one.

The first observation is OK. The second should be changed to
500 turns per lamda with a VF of 0.96.

The same principle still applies. As the turns/lamda increases,
the VF decreases while keeping the diameter and frequency
the same.
--
73, Cecil, W5DXP

On Thu, 20 Apr 2006 18:46:09 GMT, "Cecil Moore"
wrote:

What happened should be obvious.

You played the pity card. It was so obvious that I forecast that
immediately.

The second should be changed to 500 turns per lamda with a VF of 0.96.

Only 1000% off on the turns count - not bad for the first step in a
reading comprehension test. Further interpretations suffer equally.

On Thu, 20 Apr 2006 17:45:39 GMT, "Cecil Moore"
wrote:

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
That is for coil A
has a VF of 0.07.

The 50 turns per lamda
That is for coil B
has a VF of 0.86.

Let's review this response for its pity quotient:

Asked: At one length, one coil exhibits
Vf = 0.02,
reduce the coil length, what length for the SAME coil would that be
to render
Vf = 0.2
for instance?

1. We are not changing frequency;
2. we are not changing diameter/lambda
(nor in fact changing diameter OR lambda);
3. we are not changing pitch/lambda
(nor in fact changing pitch OR lambda).

Answer? Change the coil, change the Vf, and the turns/lamda.

************* W R O N G ! *****************

Draw another pity card and do not pass go.

"Richard Clark" wrote:
Asked: At one length, one coil exhibits Vf = 0.02,
reduce the coil length, what length for the SAME coil would that be
to render Vf = 0.2 for instance?

3. we are not changing pitch/lambda

So what is the pitch for one turn?
--
73, Cecil, W5DXP

On Thu, 20 Apr 2006 19:56:57 GMT, "Cecil Moore"
wrote:
So what is the pitch for one turn?

The same when there were n turns. It doesn't change with length.

When can we take the training wheels off your computer?