Cecil Moore wrote:

Tom Donaly wrote:

For someone like me, Cecil can be (but usually isn't) a very useful
crackpot. I can be pretty sure he's wrong, but the process of educating
myself into turning that hunch into a dead certainty that I can prove
to everyone (except him) can be enlightening.


Now's your chance to enlighten us, Tom. Please explain again
how the standing wave current magnitude on a 1/2WL thin-wire
dipole doesn't depend upon how many degrees it is away from
the feed point, i.e. doesn't contain any phase information.

While you are at it, please explain exactly how Kraus is mistaken
about this antenna when he plots the standing wave current as
I = cos(X) where X is the number of degrees away from the
feedpoint and feedpoint current equals 1 amp at 0 degrees.

I didn't say that the value of the standing wave current on a
1/2 wavelength dipole doesn't vary with length. I did say that
just measuring the value at some point doesn't give you all the
information you need to calculate the phase. Of course, you already
know the phase, because you defined the antenna as 1/2
wavelength, so finding any kl is trivial. Secondly, even if you're
right about the current in your antenna being a sine function, in order
to use that information, you have to measure the current input at the
current maximum - which you've already defined to be the center of the
antenna - in order to compare it with the current at the point of
interest in order to get your result. In short, you still have to
know the current at two points in order to get an answer. The
information isn't contained in just one measurement. So let me turn it
around and ask you to tell me again why you think you can get some
"phase" information from measuring a single point on an antenna
without knowing anything else about it.

I haven't read Kraus, but I expect he was talking about an idealized,
infinitely thin antenna. Add thickness to the wire, and a feedpoint gap,
and you may come up with something slightly more complicated.
73,
Tom Donaly, KA6RUH

Tom Donaly wrote:
I didn't say that the value of the standing wave current on a
1/2 wavelength dipole doesn't vary with length. I did say that
just measuring the value at some point doesn't give you all the
information you need to calculate the phase.

The subject is a 1/2WL thin-wire dipole with a feedpoint current
of 1 amp at 0 degrees as illustrated by Kraus on page 464 of
"Antennas for All Applications", 3rd Edition. That's about the sixth
time I have stated those boundary conditions.

The information isn't contained in just one measurement.

For a 1/2WL thin-wire dipole with a feedpoint current of 1 amp
at 0 degrees, as illustrated by Kraus, all the phase information
one needs to know is indeed "contained in just one measurement".

I haven't read Kraus, but I expect he was talking about an idealized,
infinitely thin antenna.

I have been very careful about specifying Kraus' 1/2WL thin-wire
dipole as the subject of this discussion. It is easiest to
understand because it has the least number of variables.

What is the agenda in trying to divert the subject away from
something easy to understand to something that is difficult
to understand?
--
73, Cecil http://www.qsl.net/w5dxp

"Cecil Moore" wrote in message
. com...
Tom Donaly wrote:
I didn't say that the value of the standing wave current on a
1/2 wavelength dipole doesn't vary with length. I did say that
just measuring the value at some point doesn't give you all the
information you need to calculate the phase.

The subject is a 1/2WL thin-wire dipole with a feedpoint current
of 1 amp at 0 degrees as illustrated by Kraus on page 464 of
"Antennas for All Applications", 3rd Edition. That's about the sixth
time I have stated those boundary conditions.

The information isn't contained in just one measurement.

For a 1/2WL thin-wire dipole with a feedpoint current of 1 amp
at 0 degrees, as illustrated by Kraus, all the phase information
one needs to know is indeed "contained in just one measurement".

I haven't read Kraus, but I expect he was talking about an idealized,
infinitely thin antenna.

I have been very careful about specifying Kraus' 1/2WL thin-wire
dipole as the subject of this discussion. It is easiest to
understand because it has the least number of variables.

What is the agenda in trying to divert the subject away from
something easy to understand to something that is difficult
to understand?
--
73, Cecil http://www.qsl.net/w5dxp

The AGENDA is to get you guys fighting! boy, sure didn't take much, even in
a thread that was obviously a troll with no technical question to start it
of! you guys are just fighting over your own statements since there was no
initial technical question or statement that started this thread... i love
it, kept me amused through a whole rainy weekend and now on a rainy
monday... supposed to rain more this week, think you guys can keep going a
bit longer??

Dave wrote:
"Cecil Moore" wrote in message
. com...

Tom Donaly wrote:

I didn't say that the value of the standing wave current on a
1/2 wavelength dipole doesn't vary with length. I did say that
just measuring the value at some point doesn't give you all the
information you need to calculate the phase.

The subject is a 1/2WL thin-wire dipole with a feedpoint current
of 1 amp at 0 degrees as illustrated by Kraus on page 464 of
"Antennas for All Applications", 3rd Edition. That's about the sixth
time I have stated those boundary conditions.


The information isn't contained in just one measurement.

For a 1/2WL thin-wire dipole with a feedpoint current of 1 amp
at 0 degrees, as illustrated by Kraus, all the phase information
one needs to know is indeed "contained in just one measurement".


I haven't read Kraus, but I expect he was talking about an idealized,
infinitely thin antenna.

I have been very careful about specifying Kraus' 1/2WL thin-wire
dipole as the subject of this discussion. It is easiest to
understand because it has the least number of variables.

What is the agenda in trying to divert the subject away from
something easy to understand to something that is difficult
to understand?
--
73, Cecil http://www.qsl.net/w5dxp


The AGENDA is to get you guys fighting! boy, sure didn't take much, even in
a thread that was obviously a troll with no technical question to start it
of! you guys are just fighting over your own statements since there was no
initial technical question or statement that started this thread... i love
it, kept me amused through a whole rainy weekend and now on a rainy
monday... supposed to rain more this week, think you guys can keep going a
bit longer??



You're welcome, Dave. Glad to oblige.
73,
Tom Donaly, KA6RUH

Dave wrote:
you guys are just fighting over your own statements since there was no
initial technical question or statement that started this thread...

Doesn't have to be. This is a continuation of earlier threads.
And I'm not fighting - I'm simply stating the laws of physics
as asserted by Balanis, Kraus, and Hecht.
--
73, Cecil http://www.qsl.net/w5dxp

yeah, i know, you guys are so busy fighting with each other that you can't
see the forest for the trees. keep going, its still raining here and may be
for a few more days yet!

"Cecil Moore" wrote in message
t...
Dave wrote:
you guys are just fighting over your own statements since there was no
initial technical question or statement that started this thread...

Doesn't have to be. This is a continuation of earlier threads.
And I'm not fighting - I'm simply stating the laws of physics
as asserted by Balanis, Kraus, and Hecht.
--
73, Cecil http://www.qsl.net/w5dxp

Dave wrote:

yeah, i know, you guys are so busy fighting with each other that you can't
see the forest for the trees. keep going, its still raining here and may be
for a few more days yet!


Dave

You obviously haven't figured out who is "fighting" and who is "amused".

I'll give you a clue, the ones fighting are "C" and "Y" hihi.

tom
K0TAR