Distributed capacitance and antennas
 

On Sun, 11 Nov 2007 05:22:21 -0800, art wrote:

Is this a prelude to your normal comment when you walk away?

Arthur, such an amusing criticism coming from you considering the
longstanding, and simple question offered to your own comment:

On Wed, 07 Nov 2007 10:56:13 -0800, art wrote:
Distributed resistance is easy, it changes the energy to heat,
stores it and releases it according to its time constant

What is the time constant of 50 Ohms?

Longwinded explanations are not sought, just a simple number (you
don't even have to show your math).

73's
Richard Clark, KB7QHC

Distributed capacitance and antennas
 

On 11 Nov, 08:16, Richard Clark wrote:
On Sun, 11 Nov 2007 05:22:21 -0800, art wrote:
Is this a prelude to your normal comment when you walk away?

Arthur, such an amusing criticism coming from you considering the
longstanding, and simple question offered to your own comment:

On Wed, 07 Nov 2007 10:56:13 -0800, art wrote:
Distributed resistance is easy, it changes the energy to heat,
stores it and releases it according to its time constant

What is the time constant of 50 Ohms?

Longwinded explanations are not sought, just a simple number (you
don't even have to show your math).

73's
Richard Clark, KB7QHC

It just goes to show that I don't have an answer to every question
that you have in your efforts to supply a platform for your jeering.
I do know that a resistor stores energy applied while it changes to
heat.
I also known that the temperature change is not instantaneous thus
time
must be a factor depending on the environment. But you present
questions
that do not deal directly with the subject posed in your attempts to
jeer.
Look at your many exchanges with Dr John E Davis, you never did
provide an
instance where the subject in hand was incorrect or otherwise. Yet
your
exchanges with him were long and so disagreeable and disrespectfull
that after several attempts while remaining polite did not line up
with
an arguement that you often want he was forced to leave.The thread has
been provided again such that other can determine whether Dr Davis was
treated with respect by you
Actually nobody including you accepted his mathematics in any way
which he proffered in an effort to show that I was correct. The only
interest of this group was to treat him the same way that they treat
outhers
on this newsgroup. I will not respond to any more of your efforts
that
defray from the discussion at hand so that you can jeer.
Art

Distributed capacitance and antennas
 

On Sun, 11 Nov 2007 08:38:38 -0800, art wrote:
What is the time constant of 50 Ohms?

Longwinded explanations are not sought, just a simple number (you
don't even have to show your math).

It just goes to show that I don't have an answer

It took you quite a while to come to same conclusion everyone else
has.

I do know that a resistor stores energy applied while it changes to
heat.

How much energy does 50 Ohms store?

73's
Richard Clark, KB7QHC

Distributed capacitance and antennas
 

On 11 Nov, 08:58, "Stefan Wolfe" wrote:
"Roy Lewallen" wrote in message

...





Stefan Wolfe wrote:
"Roy Lewallen" wrote in message
...
Stefan Wolfe wrote:

In a resonant circuit containing R, L, and C, there most definitely is a
time constant. Related to Q, it describes the time taken for the circuit
to respond to a transient. The higher the Q, the longer the time
constant, and the longer it takes the circuit to come to equilibrium
after a step or sinusoid is applied, and to decay after it's removed.
Failure to understand this has resulted in some very poorly designed
audio filters for CW, among other things.

But Roy, I must first clear up that we are talking about apples and
oranges. I was referencing a sinusoidal source of a frequency that is
resonant to the circuit. You are talking about a transient can be treated
as the sum of sinusoids which will not be resonant at the same curcuit. I
was also referring to the antenna as a L-C-R circuit that does have time
constants along its lengths (but I was asking 'where' along the length)
but as a whole system the time contant of the antenna, when fed by a
signal at resonant frequency is zero.
. . .

You've lost me. What is the meaning of a "time constant" in steady state?
What effect does it have? With a single frequency of constant amplitude,
how could you tell whether a circuit, resonant or not, has a "time
constant"? How could you measure it?

The meaning of a time constant is not dependent upon steady state sinusoids
or transient; it is merely a characteristic that dependent upon the
*physical* properties of the components in the circuit.

You know that of course.

Let us say we design a power supply for use in consumer appliances. The
power supply of course has a capacitor across line and neutral for EMI
filtering, along with a bleeder resistor in parallel with this capacitor.
Together, the bleeder resistor and phase/phase capacitor filter have a time
constant. Now the time constant is meaningless with respect to steady state
input voltage (other than wave shaping high f emi components) and with
respect to transients. It is meaningful with respect to safety. If the
consumer pulls out the plug, the bleeder resistor must discharge the phase
to phase cap safely to prevent the consumer from being shocked when touching
the L-N pins. The time constant RC in this case MUST meet certain
specifications, that is it must be less than 0.1sec. That is essentially
required legally (since standard compliance is compulsory). The time
constant exists is chosen for a worse case value, ie that the consumer
unplugs the power supply at the peak of the AC cycle.

Actually, it is the DC discharge characteristic that we care about here.
Transient suppression is not relevant nor is its ability to shape the
incoming sinusoid.- Hide quoted text -

- Show quoted text -

I read thru all and it wasn't until thelast sentence did you state
anything that is relevent. The Dc discharge characteristic
when the terminals are shorted. Discouting the spike at the
beginning the discharge is dependent on the size of the vessel
and restrictions applied by the circuit. The larger the vessel
the sharper the curve with respect to time. This goes for both
the inductance and the capacitance and it is only the losses
which are small take away the perpetual motion.
I suggest you go to google and look up a "tank circuit"
where they will I am sure take you thru the phase changes
that create the pendulum like action.
But then you knew that all along, anything but review the math.
Hot air once again. Why not discuss it with the broadcast engineer
with his long time service at switching on a transmitter every
morning,every day
plus turn the lights out. As Vanna White would say in defence of her
salary status
You have to know the alphabet
Art
Art

Distributed capacitance and antennas
 

"art" wrote
Why not discuss it with the broadcast engineer
with his long time service at switching on a transmitter every
morning, every day plus turn the lights out.
__________

As I told you once already, the last 30 years of my professional background
was in the field and applications engineering groups of the two largest
designers/manufacturers of broadcast radio and television transmitter and
antenna systems in the US: RCA and Harris.

My experience working directly for broadcast stations was early in my
career, including with a stint at WJR, a 50 kW, non-directional AM station
using a 195° monopole (700 ft high).

And what is your commercial experience in the field of r-f systems?

RF

Distributed capacitance and antennas
 

"Richard Fry" wrote in message
And what is your commercial experience in the field of r-f systems?

RF

Richard: Concerning Art's experience with RF energy, I believe
that he often microwaves with the door open.

Mike W5CHR

Distributed capacitance and antennas
 

On 11 Nov, 12:30, "Stefan Wolfe" wrote:
"art" wrote in message

ups.com...





On 11 Nov, 08:58, "Stefan Wolfe" wrote:
"Roy Lewallen" wrote in message

...

In a resonant circuit containing R, L, and C, there most definitely
is a
time constant. Related to Q, it describes the time taken for the
circuit
to respond to a transient. The higher the Q, the longer the time
constant, and the longer it takes the circuit to come to equilibrium
after a step or sinusoid is applied, and to decay after it's removed.
Failure to understand this has resulted in some very poorly designed
audio filters for CW, among other things.

But Roy, I must first clear up that we are talking about apples and
oranges. I was referencing a sinusoidal source of a frequency that is
resonant to the circuit. You are talking about a transient can be
treated
as the sum of sinusoids which will not be resonant at the same
curcuit. I
was also referring to the antenna as a L-C-R circuit that does have
time
constants along its lengths (but I was asking 'where' along the
length)
but as a whole system the time contant of the antenna, when fed by a
signal at resonant frequency is zero.
. . .

You've lost me. What is the meaning of a "time constant" in steady
state?
What effect does it have? With a single frequency of constant
amplitude,
how could you tell whether a circuit, resonant or not, has a "time
constant"? How could you measure it?

The meaning of a time constant is not dependent upon steady state
sinusoids
or transient; it is merely a characteristic that dependent upon the
*physical* properties of the components in the circuit.

You know that of course.

Let us say we design a power supply for use in consumer appliances. The
power supply of course has a capacitor across line and neutral for EMI
filtering, along with a bleeder resistor in parallel with this capacitor.
Together, the bleeder resistor and phase/phase capacitor filter have a
time
constant. Now the time constant is meaningless with respect to steady
state
input voltage (other than wave shaping high f emi components) and with
respect to transients. It is meaningful with respect to safety. If the
consumer pulls out the plug, the bleeder resistor must discharge the
phase
to phase cap safely to prevent the consumer from being shocked when
touching
the L-N pins. The time constant RC in this case MUST meet certain
specifications, that is it must be less than 0.1sec. That is essentially
required legally (since standard compliance is compulsory). The time
constant exists is chosen for a worse case value, ie that the consumer
unplugs the power supply at the peak of the AC cycle.

Actually, it is the DC discharge characteristic that we care about here.
Transient suppression is not relevant nor is its ability to shape the
incoming sinusoid.- Hide quoted text -

- Show quoted text -

I read thru all and it wasn't until thelast sentence did you state
anything that is relevent.

I really am trying to find out in what way that "time constants" are
relevant to your hypothesis or theory or whatever it is. I am surprized that
i hit something relevant. Now, you were talking about the time constant of
distributed capacitance and inductance with resistance along an antenna
radiator. I was thinking about this and I do think there "may" (or may not)
be some interesting concepts when considering an RC or R/L time contant when
the "R" is "radiation resitance"...it could be fun to think about and I will
..

But Art, how can what you have posted help me to understand why electrons
jump off the antenna wire (they are very smart because they know just when
and where to jump) and cause an effective phased array of guassian static
antennae that line themselves up in maxwelling time varying electric and
magnetic fields propagating at the speed of light, at least until
gravitational forces take over and they hit the ground :-)) ? Pardon me if
this sounds ridiculous.

That is why I say, please show me the math for whatever it is you are
proposing.

The Dc discharge characteristic
when the terminals are shorted. Discouting the spike at the
beginning the discharge is dependent on the size of the vessel
and restrictions applied by the circuit. The larger the vessel
the sharper the curve with respect to time. This goes for both
the inductance and the capacitance and it is only the losses
which are small take away the perpetual motion.
I suggest you go to google and look up a "tank circuit"

Geeze, come on Art...

where they will I am sure take you thru the phase changes
that create the pendulum like action.
But then you knew that all along, anything but review the math.
Hot air once again.

Well, it all comes from the heat stored in the resistor when the distributed
capacitance along the antenna discharges in the ohmic resistance in your 50
ohm antenna :-))) (god this is getting ridiculous)....show me your math.

Why not discuss it with the broadcast engineer

You mean some guy who learned electronics in the Navy and he 'knows all
there is to know and what he don't know ain't worth knowin' anyway'? Your
theory supposedly rises about all that! Now show us the math.

with his long time service at switching on a transmitter every
morning,every day
plus turn the lights out. As Vanna White would say in defence of her
salary status
You have to know the alphabet

I am getting ready to drop out of the conversation...the math please?- Hide quoted text -

- Show quoted text -

By all means drop out. Until somebody comes along and faults the math
I am
doomed to accept it.
Please please do as you said, that you can handle the math and prove
it in error
so I can remove myself from this mess.Many have said they can but none
have
shown that they are capable Considering all the postings on this
subject
there must have been somebody who can actually do mathematics so why
are they
reluctant to come forward. Is the math really to difficult for the
average student
or is there some fear associated with it that imposes silence?
We have college teachers among this group so certainly if it was in
error they would be quick to say so. Doesn't their absence bother you?
Just state that the math is in error as presented by Dr Davis and why
then
everything comes to a halt.
The subject which is causing anger falls completely apart when that
fact
comes to light.You ask for the math and I give you the math, what's
holding you up?
Subject closed until the math is subjected beyond the past peer review
which
states that it is accurate and correct.
Talk is just not capable of destroying the truth of mathematics.

Distributed capacitance and antennas
 

Art wrote:
"Talk is just not capable of destroying the truth of mathematics."

Math is an exact tool. A product owes more to the expertise of the
artist than it does to the tools he uses.

Best regards, Richard Harrison, KB5WZI

Distributed capacitance and antennas
 

On Sun, 11 Nov 2007 13:05:05 -0800, art wrote:

Please please do as you said, that you can handle the math and prove
it in error

Tsk, tsk, Arthur,

You cannot do as you say, yourself!

Let's consider one of your "promises:"
On Tue, 06 Nov 2007 11:04:38 -0800, art wrote:
Shorten your post and just type one line. I Richard, can show the error of your mathematics
Rr = 80 · pi² · (length/wavelength)²

73's
Richard Clark, KB7QHC

Distributed capacitance and antennas
 

Stefan Wolfe wrote:
"Roy Lewallen" wrote in message
...
You've lost me. What is the meaning of a "time constant" in steady state?
What effect does it have? With a single frequency of constant amplitude,
how could you tell whether a circuit, resonant or not, has a "time
constant"? How could you measure it?

The meaning of a time constant is not dependent upon steady state sinusoids
or transient; it is merely a characteristic that dependent upon the
*physical* properties of the components in the circuit.

You know that of course.

Let us say we design a power supply for use in consumer appliances. The
power supply of course has a capacitor across line and neutral for EMI
filtering, along with a bleeder resistor in parallel with this capacitor.
Together, the bleeder resistor and phase/phase capacitor filter have a time
constant. Now the time constant is meaningless with respect to steady state
input voltage (other than wave shaping high f emi components) and with
respect to transients. It is meaningful with respect to safety. If the
consumer pulls out the plug, the bleeder resistor must discharge the phase
to phase cap safely to prevent the consumer from being shocked when touching
the L-N pins. The time constant RC in this case MUST meet certain
specifications, that is it must be less than 0.1sec. That is essentially
required legally (since standard compliance is compulsory). The time
constant exists is chosen for a worse case value, ie that the consumer
unplugs the power supply at the peak of the AC cycle.

Actually, it is the DC discharge characteristic that we care about here.
Transient suppression is not relevant nor is its ability to shape the
incoming sinusoid.

Sorry, you've completely baffled me again. I can't find any relationship
at all between what I asked and what you wrote. There's nothing more I
can contribute, so I'll return the readers to their regularly scheduled
programming.

Roy Lewallen, W7EL