Re: Antenna physical size


"Art Unwin" <ArthurUnwin@xxxxxxxxx> wrote in message news:d898248a-13e7-4b2a-bd70-897f5917c281@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Mar 8, 12:25 am, "John KD5YI" <groups1.jo...@xxxxxxxx> wrote:
"Brian Kelly" <ke...@xxxxxxxx> wrote in message

news:806f258b-30b9-42ac-a3a6-cbad30154079@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Mar 7, 6:09 pm, Art Unwin <ArthurUn...@xxxxxxxxx> wrote:



> On Mar 7, 4:45 pm, "Dave" <no...@xxxxxxxxxxx> wrote:

> > "Art Unwin" <ArthurUn...@xxxxxxxxx> wrote in message

> >news:a0b4a425-5987-40e5-a42d-e7dacb65121f@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

> > > On Mar 7, 2:08 pm, richardharri...@xxxxxxxxx (Richard Harrison) > > > wrote:
> > > I disagree. Laws written are all based on the assumption of
> > > equilibrium and that includes
> > > Maxwell's laws. These laws hav e zero refernce to size as such > > > though
> > > many would seek

> > because contrary to what those male enhancement product adds tell you,
> > size
> > doesn't matter.

> > > for the word volume. Pertinent factors are wave length of frequency > > > in
> > > The problem here is that amateur radio is wellded to the yagi design
> > > which is not one of equilibrium

> > WAIT JUST ONE GOSH DARN MINUTE! you have said in the past that the
> > simple
> > half wave dipole WAS a prefect example of equilibrium! NOW it > > isn't???
> > have you had a new revelation while i had your old email address
> > plonked??

> David,
> You admit to not understanding the term "equilibrium" so what do you
> care what I say and in what content.
> If you consider a half wave dipole as being in equilibrium you have to
> consider the electrical circuit
> consisting of a capacitance from the antenna to ground or the route
> thru the center of of the radiator, both of thes circuits
> can be considered as being in equilibrium. However, on this newsgroup
> a fractional wavelength radiator is considered as an open circuit for
> some reason and thus under those circumstances the half wave dipole is
> not in equilibrium.
> Now your views on radiation is all over the place so it is very hard
> for me to determine the context of what you say.
> Art

Long before we rode our dinosaurs to club meetings the bright lights
had completely agreed that the strength of radio signals at far off
places was a function of the integral of i·dl where dl is the bigness
of the aerial. Maybe it's in Sears and Zemansky. I dunno . . nor do I
really care.

w3rv

Antennas for All Applications, 3rd Edition, Kraus & Marhefka, McGraw-Hill,
page 12.

<Begin quote>

Regardless of antenna type, all involve the same basic principle that
radiation is produced by accelerated (or decelerated) charge. The basic
equation of radiation may be expressed simply as

IL = Qv (A m / s)

where

I = time-changing current, A/s
L = length of current element, m
Q = charge, C
v = time change of velocity which equals the acceleration of the charge, m/s

Thus, time-changing current radiates and accelerated charge radiates. For
steady-state harmonic variation, we usually focus on current. For transients
or pulses, we focus on charge. The radiation is perpendicular to the
acceleration, and the radiated power is proportional to the square of IL or
Qv.

<end quote>

Cheers,
John

John
If Kraus said "The radiation is perpendicular to the accelleration"
then the book is worthless.
Review the scalar quantities of a radiator. It is impossible for the
resultant to be at 90
degrees to the antenna axis. I suspect the roots of this untruth was
the invention of the
planar antenna. For maximum horizontal radiation a radiator will be
around 10 degrees
out of parallel to the earth surface, not parallel.
The king is dead, long live the king. Old books just cannot keep up to
date
Regards
Art
ie the yagi


Art -

I was actually replying to W3RV. However, since you piped up...

Have you had any books on the subject published? How about research papers? Anything published at all? Do you have any presentations with equations prepared to support your claim? To which companies have you sold your expertise in this field? Have your taught any classes?

It is laughable to think anybody would consider you an authority on the subject, much less a greater authority than Kraus or any other contributor to this group. You really should get some psychiatric help to quell those delusions of grandeur you have.

Cheers,
John

.

Relevant Pages

  • Re: Loading coils: was Re: Dish reflector
    ... a higher impedance and also the condition of equilibrium. ... field measurements have cast doubt on some long-held ... of a charge or a particle of energy. ... facilities for the next radiation or application of charge. ...
    (rec.radio.amateur.antenna)
  • Re: Aerial grounding and QRM pick-up: theory & practice
    ... For most efficient radiation both the capacitance and the ... the terminals are shorted the energy is released in a burst ... Efficiency = (power applied to the antenna system - power turned into heat ... Since a half wave antenna is not in equilibrium the energy ...
    (rec.radio.amateur.antenna)
  • Re: Radiation and dummy loads
    ... fractional antenna(s) I do not knowwhen the above ... presents the means of point radiation which leads to more efficient ... any size shape or varied elevation as long as it is in equilibrium ... that this shows that the classical Gauss's law that you are trying to ...
    (rec.radio.amateur.antenna)
  • Re: Antenna physical size
    ... Maxwell's laws. ... which is not one of equilibrium ... Now your views on radiation is all over the place so it is very hard ... radiation is produced by accelerated charge. ...
    (rec.radio.amateur.antenna)
  • Re: Antenna physical size
    ... Maxwell's laws. ... which is not one of equilibrium ... Now your views on radiation is all over the place so it is very hard ... radiation is produced by accelerated charge. ...
    (rec.radio.amateur.antenna)