John Smith wrote:
John Smith wrote:
Cecil Moore wrote:
John Smith wrote:
There is SOMETHING we are ALL missing ... but, I do listen to your
arguments, I admit--I have a hard time following you ...

Well, let's take a simple example. Given a lossless
90 degree stub. What is the phase shift in the total
current from one end of the stub to the other?

Hmmm, 360? No, 180? Hmmm, 90? Well, 89.999999999999999999?

Ok, I give up, tell me ... :-)

Regards,
JS

Anyway, why current, wouldn't voltage make the same shift, although
inversely proportional?

Regards,
JS

Which, even more, bakes ones' noodle, as the same power level exists at
every single point along the length of the element, right? Seemingly,
suggesting, all points are as efficient in radiation characteristics, right?

However, I ask this while placing myself at risk of looking like an
idiot because I really am NOT sure ... oh well. But then, you already
knew, I don't know it all ... :-(

Regards,
JS

On Thu, 29 Nov 2007 17:44:39 -0600, Cecil Moore
wrote:
Jim's point is that it can be done!
In that particular coil at 4 MHz - no, it cannot be done.

On Thu, 29 Nov 2007 17:50:36 -0600, Cecil Moore
wrote:
The measured delay through my 75m bugcatcher coil is 25 nS.

In one case, the measurement "cannot be done," and in another case 6
minutes later it can be done; and the difference all because of one
"particular" coil?

That is
1. the first coil is one mighty particular coil; or
2. no measurement was done for the second, not so particular coil.

Of course, for those who readily admit that English is not their best
language of communication (and their writing tends to support that
excuse); then we could be encountering:
1. another meaning, generally unknown or archaic, for particular; or
2. another meaning, generally unknown or archaic, for measurement; or
3. both.

My bet is the answer will not hinge on blaming poor spelling, failing
eyesight, a slip in thought, or the wrong meter setting (rubber
crutches of the past), but ultimately a novel definition of the word
"measurement" which will reveal a visit to the bench is superfluous to
the conceptual clarity of it all = intellectual mooching.

Of course, a novel definition of particular would amuse us all....

On Thu, 29 Nov 2007 22:08:45 -0500, "AI4QJ" wrote:


"Richard Clark" wrote in message
.. .
On Thu, 29 Nov 2007 20:50:29 -0500, "AI4QJ" wrote:

So, in other words you agree

Hi Dan,

I use my own words, not other words, and certainly not laden with
artificial constraints and presumptions. If you want to ask a
question without all these drapes, go ahead; it is far simpler, and
consumes less bandwidth.

73's
Richard Clark, KB7QHC

OK, I will ask it like this:

On an article at http://www.w8ji.com:80/inductor_current_time_delay.htm
the author discusses time delay through an inductor.

Do you agree with the following 2 paragraphs in that article:
"How does the current travel through the inductor so fast?

At first this seems impossible, but the answer is actually quite obvious.
Time-varying current gives rise to time-varying magnetic flux. This magnetic
flux, since conductor spacing is close and the distance very small, links
the starting turn very tightly to the next turn. The rapidly changing
magnetic flux causes charges to move in the next conductor, and the changing
magnetic field couples through all the close spaced turns with very little
time delay. It is this magnetic flux coupling that provides the primary
mechanism for energy transfer through the inductor, and the path is much
shorter than the circuitous and much longer path along the conductor."

The close spacing of the coils reduces the time delays because the current
is "pushed along" faster.

Agree?

Not particularly. You got any more questions?

73's
Richard Clark, KB7QHC

On Fri, 30 Nov 2007 01:11:44 -0500, "AI4QJ" wrote:

We
will have to wait for Richard's answer to be sure, however.

Now there's a conceit, if ever one was written here.

73's
Richard Clark, KB7QHC

"Cecil Moore" wrote
Adding or subtracting loading-coil degrees is what
happens while one is tuning a screwdriver antenna.
At resonance, the screwdriver is electrically very
close to 90 degrees in length.
_______________

It may have the reactance of an unloaded ~90-degree, self-resonant radiator.
But in normal applications that doesn't make a screwdriver the radiational
equivalent of that full-sized radiator, because the radiation resistance of
the physically/electrically short screwdriver whip is less than a full-sized
antenna -- and much less on the lower bands.

A dummy load can have the reactance of a resonant screwdriver, too, but a
dummy load is not a very good antenna. I doubt you would claim that it is
electrically 90 degrees in length, just because it has the same reactance as
an unloaded ~90 degree, self-resonant monopole.

That conclusion applies to a screwdriver antenna system, as well.

RF

John Smith wrote:
Cecil Moore wrote:
John Smith wrote:
There is SOMETHING we are ALL missing ... but, I do listen to your
arguments, I admit--I have a hard time following you ...

Well, let's take a simple example. Given a lossless
90 degree stub. What is the phase shift in the total
current from one end of the stub to the other?

Hmmm, 360? No, 180? Hmmm, 90? Well, 89.999999999999999999?
Ok, I give up, tell me ... :-)

In a lossless stub, the *total current* is 100%
standing-wave current. There is zero phase shift
in the current from one end of the stub to the other.
That's why total current cannot be used to measure
a delay through a coil in a standing-wave antenna.
--
73, Cecil http://www.w5dxp.com

John Smith wrote:
Anyway, why current, wouldn't voltage make the same shift, ...

In the case of a stub, voltage could be measured.
In the case of an antenna, voltage is difficult
to measure (against ground).
--
73, Cecil http://www.w5dxp.com

John Smith wrote:
Which, even more, bakes ones' noodle, as the same power level exists at
every single point along the length of the element, right? Seemingly,
suggesting, all points are as efficient in radiation characteristics,
right?

A lossless stub doesn't radiate.
--
73, Cecil http://www.w5dxp.com

Richard Clark wrote:
In one case, the measurement "cannot be done," and in another case 6
minutes later it can be done; and the difference all because of one
"particular" coil?

Good Grief! I cannot do the measurement on the W8JI coil
because I don't have the coil. Upon the coil that I do
have, a 75m bugcatcher coil, the measurement was easy.
--
73, Cecil http://www.w5dxp.com

On Fri, 30 Nov 2007 17:09:42 GMT, Cecil Moore
wrote:

Richard Clark wrote:
In one case, the measurement "cannot be done," and in another case 6
minutes later it can be done; and the difference all because of one
"particular" coil?

Good Grief! I cannot do the measurement on the W8JI coil
because I don't have the coil. Upon the coil that I do
have, a 75m bugcatcher coil, the measurement was easy.

My goodness, it has been a long time since I've heard "Hearts and
Flowers" attempted through posting on this newsgroup. How sad! It
must be a titanic struggle to find the W8JI coil's description and
build one.

All the more strange for this shortfall given:
On Wed, 28 Nov 2007 13:25:34 -0600, Cecil Moore
wrote:
http://www.w8ji.com/inductor_current_time_delay.htm

No doubt your eyes are failing, or memory has lapsed momentarily, or
perhaps a recent personal crisis diverted your attention - or more
likely (and here we can all agree) the topic is utterly boring except
for these charming flirtations you offer (otherwise considered to be
intellectual pan-handling).

Anyway, the "suggestion" of measurement of a time delay in the quote
above is nothing more than that - a suggestion. If we were to press
for more details (always absent in these proclamations passing as
technical content), then we would find that, no, the measurement was
one of resonance (and likely not even that) which then through a weak
chain of rusty links of logic once again summons up the corrupted
reading of Corum(s) to INFER not measure.

I think the group was short-changed on the lack of a definition for
the amusing application of "particular." At least we would have
gotten some value added to drape the coffin of this thread.