"art" wrote
It has been stated on this antenna newsgroup that with
short antennas the current goes up the radiator and then turns back
and goes down. If this is so then it must be radiating all the time,
yes? If a radiator is radiating all the time then the efficiency is the
same as a full leght antenna. Yes? This does not conform with
reality Right?

Wrong, as regards your "reality." Using the classic definition of
efficiency, an antenna of ANY length (including a point source) will radiate
nearly 100% of the power it accepts from the r-f source driving it.

The radiation patterns of those antennas will vary. Some will radiate more
relative field in some directions and less in some directions than others
will. But, disregarding dielectric and conductor I^2R losses, ALL antennas
radiate ALL of the power they accept from their driving source (ie, their
efficiencies are equal).

So is it possible that the circuit (current) returns along
the path down the center of the radiator...

No, it's not possible. No matter the direction of flow along a solid
conductor, alternating current tends to travel on/near its outer surface.
This is due to the greater number of enclosed lines of magnetic flux
generated by current flowing at/near its center, which increases the
inductive reactance of the conductor in those areas. The result is a
redistribution of the current to the parts of the conductor cross-section
having the least reactance, ie, on and near its outer surface. Read
Terman's RADIO ENGINEERS' HANDBOOK, 1943 edition, pp 30-31 for more on this
(or many other sources).

IF it was possible then radiation figures accepted by hams
would coincide with respect to short antennas. Yes?.
Then why do all the "experts" reject the notion of the circuit
continueing down the center of the radiator?

Because it doesn't do that.

RF

A lot of this 'discussion' depends on how you define 'efficiency'.
A 'point source' can be very efficient, in it's self. It can also be
very inefficient when compared to another type 'source'.
It's true that any antenna can radiate all of the signal getting to
it. The 'catch' is just how much 'signal' is getting to it and how/
where is it being radiated. If it's going to where you want it, and
if a usable amount of 'signal' gets there, then it's efficient for
that particular situation. If not... then it isn't very efficient, is
it?
- 'Doc

(With the 'proper' mind-set, you can apply the above to anything, not
just antennas.)

If it's going to where you want it, and if a usable amount of
'signal' gets there, then it's efficient for that particular situation.
If not... then it isn't very efficient, is it?
- 'Doc
____________

In a pure sense, the radiator itself is.

It just may not be as useful in that application as an antenna of
another configuration that provides the system result being sought.

RF

On 11 Nov, 07:05, "Richard Fry" wrote:
If it's going to where you want it, and if a usable amount of
'signal' gets there, then it's efficient for that particular situation.
If not... then it isn't very efficient, is it?
- 'Doc

____________

In a pure sense, the radiator itself is.

It just may not be as useful in that application as an antenna of
another configuration that provides the system result being sought.

RF

There you go again, "may" does not affirm fact.
Art

"art"
There you go again, "may" does not affirm fact.
_________

OK, then.

A 1/2-wave dipole absolutely HAS more directivity than an isotropic radiator
(and so does every other practical antenna).

But when any/all of them accept the same amount of power from an r-f source,
then they ALL will radiate the same total amount of power.

So they are all equally efficient, by the classic definition of total power
in vs. total power out.

Antenna directivity/gain is not a measure of efficiency.

RF

On 11 Nov, 06:15, wrote:
A lot of this 'discussion' depends on how you define 'efficiency'.
A 'point source' can be very efficient, in it's self. It can also be
very inefficient when compared to another type 'source'.
It's true that any antenna can radiate all of the signal getting to
it. The 'catch' is just how much 'signal' is getting to it and how/
where is it being radiated. If it's going to where you want it, and
if a usable amount of 'signal' gets there, then it's efficient for
that particular situation. If not... then it isn't very efficient, is
it?
- 'Doc

(With the 'proper' mind-set, you can apply the above to anything, not
just antennas.)

I like that last comment regarding mind set. Just look how people are
not viewing the subject without predisposition. No onw is willing to
deal only what has been proffered to the exclusion of every thing
else.
Everybody will use a text gained from somewhere to side line true
examination.
Stephan,. you
wanted out I took you at your word. I don't know how many times
This discussion will end the same as always, I don't understand what
you are saying
To heck with mathematics. Iknow what I know is correct.sSme will
change the content of what I state . And as always shown in history
ridicule is turned to when all other efforts fail.
But nobody will question the fact that all computor programs support
my
addition to Gaussian law to those of Maxweell. True, other scientists
concluded
that radiation is created via a time varience. No body has found
correllation to prove it
With a legitamate addition to a known law by Gauss I have given a
method where as
the hows of radiation is revealed that is consistent with Maxwells
laws.
The mathematics have been given that support it but they have been
swept aside
Existing programs support it but it is left to the user to determine
whether
"garbage in is garbage out" or to only accept what the program
supplies with
the appearance with known reality and junk the rest.
And make no mistake about it, when programmers placed an assumed
condition
to a known law they did it with deliberation.
When it supplied error they covered it up by changing the program to
concurr
with traditional thought. This is no different to when NASA ignored
what engineers told them about O rings and science was pushed aside.
Mathematical laws were broken and all that deal with these programs
are part and parcel of this mathematical fraud.
Best regards to all
Art Unwin....KB9MZ...xg

Art wrote:
"But nobody will question the fact that all computer programs support my
addition to Gaussian law to those of maxwell."

That`s an I dare you.

Roy may tell us if EZNEC needs Art`s embellishment for accuracy.

Art did not answer my question of Nov 8, 10:27am in the "An instructive
trick" thread. It was: "why would we use the time constant without the
angular frequency?"

On page 904 0f the 3rd edition of Kraus` "Antennas" is found:
"The availability of computers in the 1960s provided antenna designers
with an alternative. They could develop software to simulate the
performance of antennas. In general, these techniques either numerically
solve Maxwell`s equations by descretizing the problem using integral
techniques, such as Moment Methods (MoM) as discussed in Sec. 14-11, or
differential techniques, such as finite elements or finite
difference-time domain."

Best regards, Richard Harrison, KB5WZI

"Richard Harrison" wrote in message
...
Art wrote:
"But nobody will question the fact that all computer programs support my
addition to Gaussian law to those of maxwell."

That`s an I dare you.

Gauss's law IS one of Maxwell's equations. In fact both Ramo Whinnery and
Van Duzer's "Fields and Waves in Communications Electronics" (pg 237 in the
1st edition) and Jackson's "Classical Electrodynamics" (compare pg 2 and 33
in the 2nd edition). So every time art makes that assertion he is just
showing his ignorance of the facts.

Dave wrote:
"Gauss`s law IS one of Maxwell`s equations."

Yes. I`ve suggested Kraus to Art but he seems not to have pored through
Kraus yet. On page 395 of the 3rd edition of Antennas is a table of
Maxwell`s equations in integral form. One column is from Ampere, another
from Faraday, and the last two are from Gauss.

Best regards, Richard Harrison, KB5WZI

On 11 Nov, 05:19, "Richard Fry" wrote:
"art" wrote

It has been stated on this antenna newsgroup that with
short antennas the current goes up the radiator and then turns back
and goes down. If this is so then it must be radiating all the time,
yes? If a radiator is radiating all the time then the efficiency is the
same as a full leght antenna. Yes? This does not conform with
reality Right?

Wrong, as regards your "reality." Using the classic definition of
efficiency, an antenna of ANY length (including a point source) will radiate
nearly 100% of the power it accepts from the r-f source driving it.

The radiation patterns of those antennas will vary. Some will radiate more
relative field in some directions and less in some directions than others
will. But, disregarding dielectric and conductor I^2R losses, ALL antennas
radiate ALL of the power they accept from their driving source (ie, their
efficiencies are equal).

So is it possible that the circuit (current) returns along
the path down the center of the radiator...

No, it's not possible. No matter the direction of flow along a solid
conductor, alternating current tends to travel on/near its outer surface.
This is due to the greater number of enclosed lines of magnetic flux
generated by current flowing at/near its center, which increases the
inductive reactance of the conductor in those areas. The result is a
redistribution of the current to the parts of the conductor cross-section
having the least reactance, ie, on and near its outer surface. Read
Terman's RADIO ENGINEERS' HANDBOOK, 1943 edition, pp 30-31 for more on this
(or many other sources).

IF it was possible then radiation figures accepted by hams
would coincide with respect to short antennas. Yes?.
Then why do all the "experts" reject the notion of the circuit
continueing down the center of the radiator?

Because it doesn't do that.

RF

To say that an AC current will not flow in copper unless it has clear
axis
access to the copper surface is balderdash. Cover the copper with an
insulator
with any thickness that you desire for safety incase you are in error
and then drill
into the center of the copper. Without a safe guard you will die!
What provides resistance on the outside als skin depth can by the
reverse contain current flow to the inside. You like many use the word
"tends"
with respect to external current flow. The word "tends" does not
make the current passage an undeniable fact. Yet you have hung
your hat on that premise. I repeat...balderdash
Art