[... snipping all the agreed to parts so far...Sorry, but all the history is
just too much…not to mention what follows! …. . . . . . . . ]



ALSO, ART. PLEASE do something to make your responses obvious in the body
of text, like line spaces, or lots of asterisks or something so I can find
your responses.



***** maybe like this



Also, you can use a word processor to compose these messages and get the
benefit of a spel chek. Hi hi , I am right now, then Cut & Paste into your
news-reader.

On to the topic…



Steve said:

So, if we change the velocity direction (to
always be tangent to the circle) , but not

the magnitude (or speed), then we
have acceleration - what we call radial acceleration.



Art:
Not sure if I follow that.



Steve: I am only describing what it takes to get motion around a circle.
It is basic physics. I'll try saying it several other ways:

The "thing" which represents the acceleration that is causing
the movement in a circle _IS_ a vector pointing toward the center of the
circle. The object is being accelerated toward the center of its orbit.
Its acceleration _IS_ directed at the center.

Another way to say it is; "In order to get the thing to travel
in a circle, you must accelerate it toward the center of said circle and
this acceleration is caused by a constant force toward the center and can be
represented by a vector pointing toward the center.

Good old F = MA is also a vector equation. That is, it can be
used to account for the direction of forces and accelerations. If the force
is in a given direction, then the acceleration is also in that same
direction. (a logical conclusion is that the acceleration is also changing
in order to remain pointing at the center as the thing moves around the
circle)

It appears that you call the acceleration one thing and the
vector another, but they are the same thing, not two different things. So
it appears to me that you are trying to make the vector something else, or
something new to get some new effect. This is where I am confused as to
just what you are thinking is the effect.





[...skipping ahead, some, but basically repeating in new terms ...]



ART:
I am saying that energy is inputed to maintain constant speed which can be
seen as creating a CONSTANT force vector at a tangent…



Steve: Yes, (in _uniform_, or constant circular motion) it takes a
constant inward force to get the constant inward acceleration which results
in the constant circular motion. HOWEVER, I have a SERIOUS problem with this
word "CONSTANT" in this context – I address below.




Steve: Moving away from the basics of uniform circular motion and on to RF
in a wire.



ART:
Yes because when the radiator is straight it is phase change that creates
cyclic current change ala accelleration.



Steve: OK, so we are back to this electron flow in a straight wire
following the sinewave in current, or "cyclic current change ", to use your
terms. Sure.

I don't under your cause and your effect here because I do not
understand what it is that you refer to when you use the words "phase
change".

It is the _generator_ (or transmitter) which is causing the
current and all the acceleration(s)...many per second. The generator
produces EMF or voltages which alternately drive current first one way, then
the other, in this sine wave fashion – along the wire. EMF (Electro Motive
Force) is call this because it acts like a force to move electrons (causing
current) in the wire. It is this force which causes the accelerations and
motions.

The generator accelerates the electrons, not what you call "phase change"--I
don't know what this means. There is a change in _current_ over time, but
NOT phase.



Art:

In the case of a circular radiator I understand that there is no phase
change a nd the radiation vector is a constant. This may well be the nubb
of the
misunderstanding.



Steve: I think there is a definite nubb here! You appear to have jumped
to DC away from RF. We should be talking about the SAME type of varying
current, therefore there is still the sinewave form of current flow, the
same accelerations. We do have an added velocity change around the circle,
but we haven't taken away the sinewave of current





Steve: I also think you are wondering if this radial acceleration does
some
special radiation that is different from the radiation of the charge
simply…



ART:

That is correct in that current variation is constant in one case and
cyclic
in the other



Steve: First, I wouldn't use phrases like "current variation is
constant". Either there is a variation, or it is constant. This phrase
implies that something is varying in a very repeatable or constant manner,
like a sine wave or square wave or triangle wave.



To answer the content of this comment, most emphatically NO! There is
always the cyclic, sinewave variation in current when you bend a current
carrying conductor into a circle. The AC sine wave doesn't go away.





Steve: I skip the area under the curve comment and continue with comments
on your cosine reference.





ART:
Yes I see the phase change as shown by the current curve.



Steve You gotta drop this "phase change" phrase. I think you simply mean
the voltage change over time, meaning the sine wave of current that is a
given in this situation.





ART:
and in the case of circular motion I do not see a phase change ( I cos
phi )





Ahhhh! OK, perhaps this direction will help. Lets talk about your
formula

I COS(phi) which is, of course I*COS(phi).



This formula gives the current at any _instant in time_ when you
plug-in that value of time. However, "phi" is NOT one number. This is
actually I*COS(wt) that's omega times "t". This is the formula, or
mathematical function of the sinewave of an AC signal of constant
frequency…just what we are talking about.



This is "I", which is the peak magnitude of the current under
discussion, times the cosine of the angle given by multiplying the frequency
(omega) by the present value of time – Which is CONSTANTLY INCREASING as
time progresses! This means that the current is constantly changing. If
you plot these values versus time on a graph, you see our friend the sine
wave and the tops and bottoms are exactly "I" high (away from zero).



Steve:
You keep mentioning "constant speed" yet we are talking, I thought,
about an antenna with RF current in it.

ART: Yes

STEVE: If this is the case, there is _NO_
constant speed of the current. It is constantly varying in a sine
wave.
It has a sinusoidal speed variation and therefore a sinusoidal
acceleration

Yes I agree. That would be of the value I cos phi with cos phi providing
the
sign wave. I believe we are saying the same thing



STEVE:

Then I am unable to understand where you are going. I see nothing new (
in regards to the basic physics above) created by the antenna being in a
circle. We just have AC flowing in a circle.



Some of the problem is your un conventional use of the terminology which
makes the transfer of the underlying concepts & ideas difficult. It is ok
to not be formally schooled in a subject. You can be what we call
"self-educated", but you must learn to use the terminology in he correct
ways (according to the way the vast majority of us use it) or you won't be
able to make yourself understood or understand others. Like I tell my
students, you MUST learn the terminology and use it correctly--- while in
both cases your head may really hurt, there is a world of difference between
a headache and a subdural hematoma!



ART: It may well be a difference of terms applied but I am pleased you
follow
the main drift of what I was saying so you could be well armed to
correct me where I was wrong.



Steve:

You go on to describe what seems to be an antenna composed of several large
horizontal, circular, or perhaps better described as helical, elements
stacked one above another, where some are wound in right-hand sense and
others in left-hand sense. I'll not go there because I believe you are
looking for some kind of a new phenomenon which is the result of this
arrangement. This may sound elitist, but I believe you are trying to
discover new physical principles with limited knowledge of the physical
world. It appears to me that your limited knowledge and ability to put
concepts to words leads you to believe there is a magic bullet just waiting
to be stumbled upon and that you can do it.

Antennas, past the simple dipole (although the basics of radiation is a
great source of confusion in itself) get complex really fast. A firm
understanding of how the currents in all parts of an antenna cause remote
fields that superimpose to cause the total, resulting field is critical to
being able to devise new and improved antennas, if they exist.

Go ahead and have fun modeling antennas. See what comes out of various
configurations. I recommend starting out simple to give yourself some
understanding of 'what' causes 'what'. Using this, build a model in your
brain (one that suits you) which ALWAYS explains all the observer phenomena
as you move along. Your model must NEVER violate any laws of physics or
fundamental principles which are known to be true. All this must also make
sense or "fit" when viewed with all other fundamental concepts, but
understand that much will be mysterious to you without this understanding.



I applaud your desire to learn and experiment, while I am sad that you have
insufficient background preventing you from seeing some of the real beauty
of the natural phenomena we call electronics.

My very best regards to you and thanks for hanging in there as opposed to
a
derogatory comment
Art.

It saddens me when I read some of what is posted. Hams are generally a very
friendly lot, but the Internet (UseNet in particular) somehow releases the
evil in some. We all have our weaker moments. Some of us are just a lot
closer to them than others. All I can do is a Tsk, Tsk and move on.



I must lead my life to a higher standard… It's a dirty job, but somebody's
got to do it.

Some people go to church and then cut you off and swear at you in traffic.
I don't do either any more.

73, Steve