Dish reflector
 

Jim Kelley wrote:
Cecil Moore wrote:

w7el "measured" the phase shift in current
that doesn't flow.

:-) He's good, but he ain't that good. Besides, his meter is the same
as yours in that it only responds to waves that travel and currents that
flow. The difference I suspect, is in the desired outcome and the
rhetoric.

Indeed.

I measured current, which as everyone with a Novice or higher grade
license should know is the rate of flow of charge(*). The charge flows
in one direction during each half cycle, and in the other during the
other half cycle, resulting in current which is positive for half the
cycle and negative for the other. This is known as "alternating
current". In fact, my measurement system (ferrite core transformers)
will only detect alternating current.

(*)We very commonly, although technically incorrectly, refer to "current
flow" when we really mean "charge flow".

Roy Lewallen, W7EL

Dish reflector
 

Roy Lewallen wrote:
I measured current (of which the definition is well understood except
apparently by Cecil), and took a lot of care to do it right. Cecil
doesn't like the result, so he's created an imaginary quantity he calls
"standing wave current" as an attempt to invalidate the results and
promote his imaginative theories. Since it's wholly his creation, its
properties are free to be modified as the immediate argument requires.

Roy is mistaken: Here is what Balanis says in "Antennas":
"The sinusoidal *current* distribution of long open-ended
linear antennas is a *standing wave* ... The *current* and
voltage distributions on open-ended wire antennas are
similar to the *standing wave* patterns on open-ended
transmission lines."

Most good fields and waves textbooks provide the equation for
standing wave current although the equation for standing-wave
voltage is more popular. I certainly did NOT invent the concept.
Why do you think a standing-wave antenna would not contain
standing-wave current?

Roy, here is a public EZNEC support request for you from
a loyal EZNEC customer.

There are 10 segments in a 1/4WL monopole over average ground.
Here is what EZNEC predicts for the currents in each segment.

EZNEC+ ver. 4.0
1/4WL vertical monopole 4/17/2009 6:46:08 PM
--------------- CURRENT DATA ---------------
Frequency = 7.29 MHz
Wire No. 1:
Segment Conn Magnitude (A.) Phase (Deg.)
1 Ground 1 0.00
2 .97651 -0.42
3 .93005 -0.83
4 .86159 -1.19
5 .77258 -1.50
6 .66485 -1.78
7 .54059 -2.04
8 .40213 -2.28
9 .25161 -2.50
10 Open .08883 -2.71

There's about 9 degrees per segment so the number of degrees
between segment 3 and segment 7 is about 36 degrees. If you
put your current probes on segment 3 and segment 7, you will
measure a 1.21 degree phase shift in those 36 degrees of
antenna (just as you did in 36 degrees of loading coil). How
do you explain how to accurately measure the number of degrees
in a wire given EZNEC's numbers? Why do you think a coil is
any different from a straight wire?

As I, Jim, other posters, and all good texts have explained, a standing
wave describes the amplitude envelope of a voltage or current, as a
function of position, which results from interference between traveling
waves.

The total current is sometimes parsed into a standing wave plus
a traveling wave. In a standing-wave antenna like a 1/2WL dipole,
the standing wave current is about 90% of the total current while
the traveling wave current is about 10% of the total current.

Total wave = forward traveling wave + reflected traveling wave.

Total wave = standing wave + traveling radiated wave

There's no such thing as "standing wave current". You'll find no
references to this fictitious entity in any electromagnetics text.

Absolutely false. In "Fields and Waves in Modern Radio".
by Ramo and Whinnery, 2nd edition, page 42, it gives the equations
for standing wave voltage and standing wave current. The current
equation is: I = (e^jwt/Z0)[Vfor*e^-jbz - Vref*e^+jbz]
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Dish reflector
 

Roy Lewallen wrote:
I measured current, which as everyone with a Novice or higher grade
license should know is the rate of flow of charge(*). The charge flows
in one direction during each half cycle, and in the other during the
other half cycle, resulting in current which is positive for half the
cycle and negative for the other. This is known as "alternating
current". In fact, my measurement system (ferrite core transformers)
will only detect alternating current.

Roy, you once verified that the phase of the total current
on a 1/2WL dipole changes by less than 10 degrees over the
entire 180 degree length of antenna. How can you use a current
that changes phase by only 10 degrees in 180 degrees of antenna
to measure the delay along the wire? If you cannot do it along
a wire, what makes you think you can do it through a loading
coil.

For the readers who don't know, Roy absolutely refuses to answer
any of my questions like the above.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Dish reflector
 

Roy Lewallen wrote:
I measured current (of which the definition is well understood except
apparently by Cecil), and took a lot of care to do it right.

Here is a challenge for you, Roy. Set up a short resonant
1/2WL dipole. Install your current pickups 1/3 and 2/3 of
the way from the feedpoint. Obviously that will be 30 degrees
of antenna.

Measure the phase shift between those two points using
the same care as you used with the loading coil.

I'll bet you $100 that you will not measure a 30 degree
phase shift. EZNEC says it will be closer to 3 degrees.

What would be your conclusion if you indeed did measure
3 degrees as EZNEC predicts?

P.S. Would someone please forward this to Roy since he
has Plonked me and refused my emails?
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Dish reflector
 

On Apr 17, 7:07*pm, "Dave" wrote:
"Art Unwin" wrote in message

...
On Apr 16, 9:48 pm, Cecil Moore wrote:

I don't worry about it Cecil but I am concerned at the number of
people who consider themselves engineers. Remember that nobody on this
group has a true understanding of Maxwells equations! Nobody has
proved Maxwell's laws can be proved by adding a time varing field to
the Gaussian law of Statics. In fact, it is denied by ALL on this
group, Engineers?

yes art, electrical engineers, like me, do understand maxwell's equations..
and any of them worth their salt will explain, like i have done many times,
that it is unecessary to add an explicit time variable to the equations
because they are valid at every instant of time... so you end up with
f(t)=f(t) which is redundant and doesn't help with the solution of the
fields and waves. *you have admitted that you don't know fields and waves
and that you are not an ee, yet you continue to try to put down those who
show a true understanding of the equations and their underlying assumptions.
Hello David
I am comfortable that the addition of a time varying field to the laws
of statics is a proof of Maxwell. In fact there are many proofs of
Maxwsells equations if you read your field and waves books Chapter 2
if I recall as well as the appendix. Dr Davis also stated so and
nobody was able to prove him wrong either. So as I have always said I
am comfortable with the proof.




you further demonstrate this by talking about lumped impedances in reference
to maxwell's equations and antennas. *maxwell's equations describe fields
and waves, not the conductors and elements that generate them. *they
reference the currents and fields, not the wires, capacitors, and inductors.
you can derive the properties of inductors and capacitors from maxwell's
equations, but you have to look deep inside them and apply the basic laws
that make up maxwell's equation to describe the lumped elements.

Well again I disagree with you. Maxwells laws as far as we are
concerned deals with radiation and maximum efficiency with the basic
of equilibrium. As Newton used the term it was a cosmic law as is all
his laws thus equilibrium or balance is based on the cosmic which
includes outside Earths sphere, a basic for every action and reaction
statement. When you introduce a lumped load into radiation without the
equal and opposite you have violated Maxwell and Newtons laws, very
simple. This is why Maxwell does not include a metric for lumped loads
when calculating maximum efficiency via the boundary method.
Now as far as waves are concerned science recognises that radiation
presents observations that suggest waves but none of these are proven
and I believe that particles dominate which if you go along with
statics laws is also another proof.





you have yet to explain where equilibrium is required in maxwell's
equations. *by definition they rely on non-equilibrium conditions to set up
waves. *you can't have a wave while you are in equilibrium, something has to
be putting energy into the system and something has to be moving, that
sounds like non-equilibrium to me.

Not so, review the gyroscope action and the sedgewick vehicle all of
which rely on balanced circulating rotation within the cosmos.
But disregard all the things above that you cannot digest. Use a
computer program on antennas that has the option to change human input
so that the laws of Maxwell
are fiollowed implicity. You put in a vertical design and request
maximum gain using the parameters supplied by Maxwell which requires
cosmic balance or equilibrium.
Antenna computer programs will always put aside the planar design as
it lacks equilibrium and will replace it with a tipped vertical
antenna.
So David you have now put your feet into another puzzle by your falure
to digest science. Science and the patent office accept antenna
computer programs output
which is opposite to your thinking so now you are surrounded by a
morass because you denied the good Doctors knowledge of physics.
I accept that that you and others do not have a good understanding of
equilibrium which generates faults in all associated science problems
so our minds will never meet. If you delve into books on Maxwell you
will eventually fall upon the use of Gauss. Since there are so many
proofs available authors shun from showing the Gaussian connection
because of the different metrics involved not because it is not a
viable proof. You have a simple option to prove what is correct, use a
antenna program with an optimiser and determine what a vertical
antenna looks like when seeking maximum efficiency, believe me the
radiator will be tipped. So forget every thing else and show the World
why computer programs produce faulty results when using your logic.
With the use of my logic I have produced a antenna for top band that
is rotatable and directional so something I have done is correct and
computer programs based on Maxwell produce the same results. Go
figure.
Now with respect to a dish antenna with CP. Can the dish supply a
lower TOA than a planar design at the same height?
Regards
Art.
Ps Mechanical engineering requires adherence to equilibrium, it is not
just a electrical thing.I also know little regarding fields and waves
but I am profficient in the application
of fields operating at the speed of light and their impact on
particles for communication
and where impact requires mass.

Dish reflector
 

"Art Unwin" wrote in message
...
On Apr 17, 7:07 pm, "Dave" wrote:

Well again I disagree with you. Maxwells laws as far as we are
concerned deals with radiation and maximum efficiency with the basic
of equilibrium.

Maxwell's equations say nothing of efficiency. Nor do they mention
equilibrium.

Not so, review the gyroscope action and the sedgewick vehicle all of
which rely on balanced circulating rotation within the cosmos.

you like your mechanics... best to stick with them, you don't understand
fields and waves at all.


Science and the patent office accept antenna
computer programs output

the patent office accepts designs for faster than light antennas also. that
doesn't prove that there is any science behind them at all.


If you delve into books on Maxwell you
will eventually fall upon the use of Gauss.

Gauss is basic to the Maxwell equations, as i pointed out by it being used
within the first few pages of Jackson.

believe me the radiator will be tipped.

only as far as your brain has tipped.

something I have done is correct and
computer programs based on Maxwell produce the same results.

right, next you'll be rewriting the bible.

Ps Mechanical engineering requires adherence to equilibrium

if a mechanical system is in equilibrium how much work does it do?

Dish reflector
 

Roy Lewallen wrote:
I measured current (of which the definition is well understood except
apparently by Cecil), and took a lot of care to do it right.

Roy, I am not questioning the accuracy of your
measurements - I'm sure they are extremely
accurate.

What I am questioning are your concepts and
conclusions about those measurements.

As illustrated in Kraus' antenna book, the end-
to-end current phase changes by about 3 degrees
for a 1/2WL dipole or a 1/4WL monopole. My question
for you is:

How can a current that changes phase by 3 degrees
in 90 degrees of antenna possibly be used to
determine the delay through the antenna wire?
- or through a loading coil?

Hint: The current in a standing wave antenna is of
the form:

I(x,t) = C1*cos(bx)*cos(wt) + C2*cos(wt+bx)

where C1 C2

i.e. the phase changes primarily with t but primarily
not with x. For any time t, the measured phase up and
down the antenna changes very little.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Dish reflector
 

On Apr 18, 10:30*am, "Dave" wrote:
"Art Unwin" wrote in message

...
On Apr 17, 7:07 pm, "Dave" wrote:

Well again I disagree with you. Maxwells laws as far as we are
concerned deals with radiation and maximum efficiency with the basic
of equilibrium.

Maxwell's equations say nothing of efficiency. *Nor do they mention
equilibrium.

Not so, review the gyroscope action and the sedgewick vehicle all of
which rely on balanced circulating rotation within the cosmos.

you like your mechanics... best to stick with them, you don't understand
fields and waves at all.

Science and the patent office accept antenna
computer programs output

the patent office accepts designs for faster than light antennas also. *that
doesn't prove that there is any science behind them at all.

If you delve into books on Maxwell you
will eventually fall upon the use of Gauss.

Gauss is basic to the Maxwell equations, as i pointed out by it being used
within the first few pages of Jackson.

I suppose that Gauss has a law that is basic to Maxwells laws but
certainly not his law of statics. That particular law is two dimension
which does not include time.
Another scientist supplied to him a similar law that was also two
dimensional and it was that law provided the clue which required
clarification such that the two dimensional findings had to be added
to to match the metrics of equilibrium as required by Newton. If
Newton had not required uniformity of metrics it is quite possible his
laws would not have been corrected until the discovery by Foucault
which Maxwell had deduced or predicted as being present before
Foucault was born.
That force was determined as being the weak force by me which is
required for the grand unification theory (GUT) which unites all the
sciences of nature which includes the electricity matter which you
have boxed as being isolated from classical physics as we know it.
Frankly David, you have over estimated your value as a engineer by
your neglect of physics
Regards
Art







believe me the radiator will be tipped.

only as far as your brain has tipped.

something I have done is correct and
computer programs based on Maxwell produce the same results.

right, next you'll be rewriting the bible.

Ps Mechanical engineering requires adherence to equilibrium

if a mechanical system is in equilibrium how much work does it do?

Dish reflector
 

Jim Kelley wrote:
Cecil Moore wrote:
It's *energy* in the traveling wave that gets radiated.
Less energy indeed lowers the current amplitude.

Agreed.

Note that we agree on almost everything.

w7el "measured" the phase shift in current
that doesn't flow.

:-) He's good, but he ain't that good. Besides, his meter is the same
as yours in that it only responds to waves that travel and currents that
flow. ... I've said my piece.

Exactly, the more you post, the more obvious agreements
we have. The following current is the one that dominates
a standing-wave antenna.

I(x,t) = Imax*cos(kx)*cos(wt)

Such a current cannot be used to calculate delay from
phase shift in a wire or in a coil. Yet, that is exactly
what w7el and w8ji did.

Are you leaving the thread because you are on the verge
of proving w7el wrong?
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Dish reflector
 

"Art Unwin" wrote in message
...
On Apr 18, 10:30 am, "Dave" wrote:
I suppose that Gauss has a law that is basic to Maxwells laws but
certainly not his law of statics. That particular law is two dimension
which does not include time.

THE Gauss's law is one of the 4 basic maxwell's equations, and it definately
is 3d.