On 1 Dec, 13:44, Owen Duffy wrote:
"AI4QJ" wrote :

Hi Owen,

First of all I said in the post that I was using EE101. Skin effect is
somewhere in EE201; it is not generally considered necessary to
consider RF skin effect when explaining fundamental principles. After

Tom reported the measured Q of the coil... you didn't need to calculate R
from first principles.

you brought it up I merely went on to illustrate that no matter what
worse case skin effect you could resonably think of, the phase angle

No, you guessed could it be twice, quadruple. A Max Smart approach,
"would you believe... ". Tom's measurements suggest over ten times.

Sure, even at ten times, it doesn't affect your result, but it does speak
to the rigour of your analysis.

will still be essentiall 90 degrees for all practical purposes. When
talking about the COIL (not a mobile antenna system at 4MHz), it was
important for the sake of discussion to be talking about 90 degrees
because a true amateur antenna will be not be so perfect. The
discussion at hand was W8JI's coil, not an antenna.

At the end of the day, it appears to me you are working up the
relationship between the phase of the current through the coil with
voltage across the coil, and you seem to regard the phase of the current
to be uniform at all points in the coil.

If I understood Tom's article correctly (and it too is short on detail),
he is comparing the phase of the current at one end of the coil with the
phase of the current at the other end of the coil.

You are not on the same page!

But, as I said, the rigour isn't there for what is being touted as just a
maths problem.



Agreed, it is not an unfamiliar technique to make reasonable
assumptions when illustrating a point. Thank you for the opportunity
to confirm my assumptions valid in this case.

No, I did not confirm anything. Now that you force the issue, I disagree
with most of what you said in the posting to which I responded.

Owen

Cecil,
Nobody here is willing to say they were wrong. It is not education
that they demand, just a place on the net where they can complain.
If collectively they debated point by point and resolving as they
move along things could be solved. But that is not on the agenda
or addresses their needs. All just want to be on the majority side
if a poll is taken for security.
Art