RSGB RadCom December 2007 Issue
 

"Stefan Wolfe" wrote in message
...

"Mike Kaliski" wrote in message
...

Integral calculus has been described as one of the greatest advances in
mathematical science, but that is still only an approximation method and
nobody complains about that.

Mike, it is hard for me to let this go (but it is off topic). Integral
calculus is not an approximation, it is exact. The prior art, the
summation method of adding the areas of small rectangles, was the
approximation. The genius of integral calculus was that it was able to sum
an infinite number of infinitely small rectangles and come up with an
exact answer. For the answer to be exact, it was necessary to deal with
infinity (undefined) and the concept actually works. It even works in many
cases where there is an asymptote that is infinitely long (f(x) =
1/x**2)).
END OF COMMENT (no, I will not offer experimental proof that integral
calculus is exact :-))
Stefan

All true and it works very well. It's just that being forced into accepting
such concepts as infinity and the square root of minus one without being
able to pin down exactly what they are shows up how limited we are in our
abilities to deal with the true nature of the universe. How can anyone
really get to grips with such concepts as an infinity of infinities?

Mike G0ULI

RSGB RadCom December 2007 Issue
 

art wrote:
By the same token I am challenging to prove the
veracity of the additional statement that a sino
soidal current is present at every segment point.

If one threads a toroidal transformer over
a dipole wire, one will observe a sinusoidal
waveform (if the source is sinusoidal).
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Stefan Wolfe wrote:
"Tom Donaly" wrote:
Have you verified this experimentally, Cecil? If you did,
how did you do it?

This work has already been done.

Thanks Stefan, Tom apparently believes I should
reinvent the wheel every time I ride my Harley. :-)
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Richard Clark wrote:
The old saw of dipoles not needing a ground (one of those things that
makes them so much "better" than verticals) is confounded because they
do need a ground - if you want more gain.

What's the difference in free space gain between a
vertical dipole and a horizontal dipole? :-)
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

On Nov 15, 2:41 pm, Cecil Moore wrote:

Reflections occur only at physical impedance
discontinuities.

Richard Feynman said there is a probability that reflection will occur
at any point within a partially reflecting media. He explained that
all the probabilities (including phase) sum in order to generate the
net, observed effect. Your observation about the full-wave loop is
probably a good example.

73, ac6xg

RSGB RadCom December 2007 Issue
 

John Smith wrote:
"From the above, are the two in a constant state of interaction?"

On page 1 of Terman`s "Electronic and Radio Engineering":
"These waves, which are commonly called radio waves, travel with the
velocity of light and consist of magnetic and electric fields that are
at right angles to each other and are at right angles to the direction
of travel. If these electric and magnetic fields could actually be seen,
the wave would have the appearance indicated in Fig. 1-1."

Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

The alternating magnetic field creates an alternating electric field in
the space surrounding it. Due to the alternation of the electric field
an alternating displacement current will exist in space, which will give
rise to another alternating magnetic field in the space surrounding the
displacement current, etc., etc., etc..

Maxwell`s proof is courtesy B. Whitfield Griffirh, Jr.`s
"Radio-Electronic Transmission Fundamentals", now in reprint by Scitech
Publidhing, Inc..

Best regards, Richard Harrison, KB5WZI

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:

...
The alternating magnetic field creates an alternating electric field in
the space surrounding it. Due to the alternation of the electric field
an alternating displacement current will exist in space, which will give
rise to another alternating magnetic field in the space surrounding the
displacement current, etc., etc., etc..

Maxwell`s proof is courtesy B. Whitfield Griffirh, Jr.`s
"Radio-Electronic Transmission Fundamentals", now in reprint by Scitech
Publidhing, Inc..

Best regards, Richard Harrison, KB5WZI


Richard;

Thanks for taking the time to post that data.

Of course, in my "addled way of thinking", I still see the probability
of a media in which these actions are taking place (electric to magnetic
and magnetic to electric )--such as when you swing a wire (media)
through a magnetic field.

But, really, it is all still a question ... anyway, pondering keeps me
outta the bars. :-)

Regards,
JS

RSGB RadCom December 2007 Issue
 

Jim Kelley wrote:
Richard Feynman said there is a probability that reflection will occur
at any point within a partially reflecting media.

Of course, there are always 2nd, 3rd, ... Nth order effects.
On this newsgroup, we are usually talking about first order
effects. I had a recent email exchange with someone talking
about the part of the ground wave that escapes absorption
because of the earth's curvature and is probably ignored
by NEC simulators but not by AM broadcasters.
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:
Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

Does this cause and effect chain of events result in a
phase lag between the electric and magnetic fields?
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

On 16 Nov, 10:38, Cecil Moore wrote:
Richard Harrison wrote:
Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

Does this cause and effect chain of events result in a
phase lag between the electric and magnetic fields?
--
73, Cecil http://www.w5dxp.com

I would like more than that!
I would like to know what Terman had to say about radiation
which is a cause of most discussion the summation of which
is not accepted by the IEEE. I don't think he has given any
credit to Maxwell, Faraday, Heaviside or any of the pioneers
in any of his books so it would be interesting to know why
his wrestling with the mechanics of radiation was to no availe!.
And Richard, when you have finished reading from Terman
to get us to sleep, would you consider for your next book
to read to us, like Lady Chatterlies Lover by D.H. Lawrence?
That book may well prevent you going to sleep as well while
reading on the net Most of us have read all the volumes by
Terman so a different reading book may well be of more interest.
Art