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  #191   Report Post  
Old September 8th 03, 01:21 AM
Dave Shrader
 
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I have not followed the whole thread, but at the bottom line, the impact
of a complex Zo on power is an attenuation factor. It can be shown as
follows.

The general equations a

Vf = [[(R+jwL)/(G+jwC)]^0.5]*If

Vr = [[(R+1wL)/(G+jwC)]^0.5]*Ir.

A numerical example for typical 50 ohm cable at 30 MHZ follows:

Assume C = 30E-12 F/ft. Therefore L = 0.075E-6 H/ft [50 ohm lossless].

Assume 1/R [G] 1E-8 [100 megohms][lossy dielectric]

Finally, assume R = 10 ohm [moderate rf resistance].

The resulting Zo for the assumed conditions is
[[(10+jw7.5E-8)/(1E-8+jw30E-12)]^0.5] ohms.

|Zo| = [[(10+j14.137)/(1E-8+j0.00565)]^0.5] = 55.360 ohms.

Determine the relative phase shift as follows:

atan[10+j14.137] = 54.7257 degrees.

atan[1E-8+j0.00565] = 89.99989859 degrees [approximately 90].

The relative phase shift for the assumed complex Zo at 30 MHZ is 54.7257
- 89.99989 degrees [35.274 degrees].

Result: Zo = 55.360 ohms @ 35.274 degrees.

Therefore Vf = If*[55.360 degrees]

Therefore Pf(load) = Vf(source)*If(source)*cos(35.274) = 81.63% of maximum.

The transmission line does not care if the signal is left to right or
right to left; or forward and reflected. The effect is to introduce a
mirror image to both the Vr and Ir terms.

I hope I have not been redundant to other posts on this thread!

Deacon Dave, W1MCE


  #192   Report Post  
Old September 8th 03, 06:16 AM
pez
 
Posts: n/a
Default

"Richard Clark" wrote in message ...
|
| Hi Fellows,
|
| Such intense interest and no comments to SV7DMC for his work to this
| matter?
|

Dear Mr. Richard Clark,

Thank you very much for your kind interest!

You have absolutely right.
It's a pity indeed
but unfortunately
there are but very few comments for our point of view.
However at least,
all of them which are centered on the heard of the matter,
I have a feeling that,
are rather positive.
I hope.
Perhaps we have to put the blame
on this damned language barrier.
Who knows?
Too much silence...

Sincerely yours,

pez
SV7BAX

P.S.
Permit me please to correct you on that:
It is not "his work" but "her work".
  #193   Report Post  
Old September 8th 03, 07:05 AM
pez
 
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Dear Mr. Richard Clark,

Here it is, once again!
I do my best but it happens constantly.
As I just told you for the Language Barrier,
now it is
"The heart of the matter",
not
"The heard of the matter".
But I keep try...

Sincerely yours,

pez
SV7BAX

  #194   Report Post  
Old September 8th 03, 03:52 PM
Cecil Moore
 
Posts: n/a
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Dr. Slick wrote:
Cecil Moore wrote:
Yes, the pair that satisfies the conservation of energy principle
including source power and losses in the feedline. For instance,
if a load is accepting 100 watts when the power reflection coefficient
is 0.25, Pfwd(0.75) = 100W, so Pfwd = 133.33W, Pref = 33.33W.


From Pozar: For a lossless 2-port network,
[s11]**2 + [s21]**2 = 1
0.25 + 0.75 = 1
So hopefully this would be a lossless, passive network.


Yes, the above is from an earlier lossless Z0-matched example.

If any heat was generated in this passive network
(NOT the load, the network itself), then the sum of the power
reflection coefficient and the power transmission coefficient would
be less than one.


My example was the impedance discontinuity point between 50 ohm
feedline and 150 ohm feedline. Not much room for losses in 0.1"
of copper.
--
73, Cecil http://www.qsl.net/w5dxp



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  #195   Report Post  
Old September 8th 03, 06:40 PM
Richard Clark
 
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On Mon, 8 Sep 2003 08:16:34 +0300, "pez" wrote:

P.S.
Permit me please to correct you on that:
It is not "his work" but "her work".


Hi,

I am at a loss for the equivalent to OM in your regard, and initials
do mask you further. I should have been able to surmise this
essential difference from your listing on Buckmaster.

Another essential difference is that you performed the work that
others simply meander around in the hopes of being mistaken as
workers.

Myself, I cannot task myself to publish complete derivations for two
reasons. One, very few here are here to resolve anything but a
sagging ego - hence the lack of standards in maintaining a progressive
dialog. Two, I abide by a maxim that if one cannot express the key
argument to the limited confines of one screen, then that argument
lacks focus. I hope you do not take this as a diminution of your
work, but more as a statement of stylistic variation. Keep up your
effort, you are doing well.

73's
Richard Clark, KB7QHC


  #196   Report Post  
Old September 8th 03, 11:56 PM
Roy Lewallen
 
Posts: n/a
Default

pez, your English is no barrier. It's better than many Americans posting
on this and other newsgroups. The "language" of the "language barrier"
here is the language of mathematics. Some of the posters who have been
the most verbal and insistent don't seem to able to deal with the math
necessary to understand the concepts involved, so they're reduced to
arguments which can't be mathematically demonstrated.

Roy Lewallen, W7EL

pez wrote:
"Richard Clark" wrote in message ...
|
| Hi Fellows,
|
| Such intense interest and no comments to SV7DMC for his work to this
| matter?
|

Dear Mr. Richard Clark,

Thank you very much for your kind interest!

You have absolutely right.
It's a pity indeed
but unfortunately
there are but very few comments for our point of view.
However at least,
all of them which are centered on the heard of the matter,
I have a feeling that,
are rather positive.
I hope.
Perhaps we have to put the blame
on this damned language barrier.
Who knows?
Too much silence...

Sincerely yours,

pez
SV7BAX

P.S.
Permit me please to correct you on that:
It is not "his work" but "her work".


  #197   Report Post  
Old September 12th 03, 12:02 AM
Richard Clark
 
Posts: n/a
Default

On Thu, 11 Sep 2003 12:13:44 +0300, "pez" wrote:

Dear Mr. Richard Clark,

Thank you for the encouragement and your kind words.
but I am not so sure that we deserve them (*).


Hello,

Your manners are superlative, and far better than my own manners
(according to others, and that's fine as this is a characteristic of
my aggressive style).

Yes, you have absolute right about the initials, etc.
But this became the motivation
to discover, with a great deal of surprise I admit,
that someone has given a bunch
of inaccurate details to this site.
We do not have something to hide


You offer your call sign, that is far more unique than any signature
that may be applied (like Dr. Slick). We have (as I am sure your part
of the world does also) a history of pseudonyms or nom-de-plume for
writers who wish to obscure their identity. I take care to write
everything such that I can accept responsibility - or take
responsibility. Many here do so too. Others do not, but in this day
and age, anonymity is not guaranteed (again, taking the example of our
same Dr. Slick) nor is it an affront if the writer commits to dialog
and not simply slander or attack. Such occurrences of attack are rare
here, and generally ignored.

therefore we certainly do not belong to those
with an extremely sensitive interest
on private data.
But I have to wonder:
is there any responsibility
by the site owner
to guard the amateurs' personal data
from anybody's will?


Well, if by "site owner" you mean this newsgroup, then there is no
"owner." There are nearly 40000 newsgroups that simply exist by
nature of a combination of news-servers that are interconnected and
sharing a protocol called NNTP. This protocol has been around since
the beginning of the Internet (long before the WWW). It is like the
public square where people meet to talk and listen and as in that
square, if you are recognized, others will call you by name and
perhaps comment about your ancestors. Such is privacy.

Just as anything may be written here for free, anything written here
has no intrinsic value. Value comes through association to the writer
and that writer's continuity of thought and logic.

You are already establishing a very good continuity and achieving a
good association - to those who care!

Finally,
I do share your point of view for the length of a message
and I try to keep them as short as possible
but anyhow,
take a look please
on their rejection (*)
in the related thread
of our lengthy, indeed, derivations...

do;^)

Sincerely yours,

pez
SV7BAX


Rejection is the forge of ideas. It does not condemn your work, it
merely marks the critic by the nature of their criticism. If that
criticism is weak, so is the critic. If that criticism is strong (not
abuse, not refusal), then your argument is weak. Being technically
and mathematically correct is not necessarily strength in an argument.
You may be quite accurate, but the message is obscured by the bulk of
presentation.

A Canadian social scientist, Marshall McCluhan, demonstrated that
identical material presented through different media become different
messages. For instance, if you were to present you material to a
class, they would accept it and work through it for understanding. If
you were to present it to that same group of students in the public
square, some might scoff, others might wander off with indifference.
If you were to present it on TV, you probably wouldn't even make it to
the first commercial. If you presented it on radio, you might have a
highly interested audience. Same material, different venues,
different responses.

The same goes here. The nature of newsgroups is with dialog and
hopefully you exchange correspondence with those who will allow you to
develop your idea and stick with you to the end. If you attempt to
make one presentation that answers all questions in one place, it
violates a social contract that excludes them - except for them to
accept or reject your work. They are not here to submit. This means
you have to allow a style that is dialog in nature that allows their
questions along the way to the end, where you do not find yourself
wandering down the wrong path. (Think of the Socratic or Platonic
methods of argument.) Unfortunately there are those who will
manipulate discussion to the wrong path, or confusion. Dialog over
time will reveal these individuals. This is why "lurking" is advised
to newcomers so that they recognize personality with the signatures.

One last point. Nothing is done once here. Nothing is solved.
Nothing is fixed. The message will need repeating if only because new
participants have not read the first message. The message may need
repeating because you did not convince your critics, but they have had
more time to ponder. This means that you sometimes have to vary your
style and presentation so that repeating is not ignored. If you
absolutely need the lengthy, mathematical treatment, then publish it
at a web site and make a reference to it in your discussion. Offering
the complete mathematical treatment each time you write here
automatically limits you and reduces your audience. The craft of
writing is knowing what to throw away. I generally discard 3/4ths of
what I write before I hit the send button (some may groan not enough
was thrown away here ;-)

73's
Richard Clark, KB7QHC
  #198   Report Post  
Old September 12th 03, 03:37 PM
pez
 
Posts: n/a
Default

Dear Mr. Richard Clark,

What can I say?

This is the fourth time,
I have to call on my inadequate English
to justify a misunderstanding.
And this time
it is related to the Buckmaster site
mentioned by you
and that's all.

As for the rest three quarters of your message,
I don't feel that I am in position
to make any comment
since they are looking to me
as advises to successful advertisers.

But, there is one point
which, remarkably enough,
is referenced by you in both of your letters
and about the bottom line of them.
It has to do with the matter
of "maths" publication.
Noticeably,
you show about this matter
a strong predilection to web site publication
and a rejection of any inclusion into newsgroup messages.
Although for the moment
is seems that the right is on your side,
at the same time,
a recall to the need for direct communication
surpasses any other argument.
After all this is the deepest reason
for newsgroups existence, I believe.
Anyway.

Thank you very much for your time.

Sincerely yours,

pez
SV7BAX

"Richard Clark" wrote in message ...
| On Thu, 11 Sep 2003 12:13:44 +0300, "pez" wrote:
|
| Dear Mr. Richard Clark,
|
| Thank you for the encouragement and your kind words.
| but I am not so sure that we deserve them (*).
|
| Hello,
|
| Your manners are superlative, and far better than my own manners
| (according to others, and that's fine as this is a characteristic of
| my aggressive style).
|
| Yes, you have absolute right about the initials, etc.
| But this became the motivation
| to discover, with a great deal of surprise I admit,
| that someone has given a bunch
| of inaccurate details to this site.
| We do not have something to hide
|
| You offer your call sign, that is far more unique than any signature
| that may be applied (like Dr. Slick). We have (as I am sure your part
| of the world does also) a history of pseudonyms or nom-de-plume for
| writers who wish to obscure their identity. I take care to write
| everything such that I can accept responsibility - or take
| responsibility. Many here do so too. Others do not, but in this day
| and age, anonymity is not guaranteed (again, taking the example of our
| same Dr. Slick) nor is it an affront if the writer commits to dialog
| and not simply slander or attack. Such occurrences of attack are rare
| here, and generally ignored.
|
| therefore we certainly do not belong to those
| with an extremely sensitive interest
| on private data.
| But I have to wonder:
| is there any responsibility
| by the site owner
| to guard the amateurs' personal data
| from anybody's will?
|
| Well, if by "site owner" you mean this newsgroup, then there is no
| "owner." There are nearly 40000 newsgroups that simply exist by
| nature of a combination of news-servers that are interconnected and
| sharing a protocol called NNTP. This protocol has been around since
| the beginning of the Internet (long before the WWW). It is like the
| public square where people meet to talk and listen and as in that
| square, if you are recognized, others will call you by name and
| perhaps comment about your ancestors. Such is privacy.
|
| Just as anything may be written here for free, anything written here
| has no intrinsic value. Value comes through association to the writer
| and that writer's continuity of thought and logic.
|
| You are already establishing a very good continuity and achieving a
| good association - to those who care!
|
| Finally,
| I do share your point of view for the length of a message
| and I try to keep them as short as possible
| but anyhow,
| take a look please
| on their rejection (*)
| in the related thread
| of our lengthy, indeed, derivations...
|
| do;^)
|
| Sincerely yours,
|
| pez
| SV7BAX
|
| Rejection is the forge of ideas. It does not condemn your work, it
| merely marks the critic by the nature of their criticism. If that
| criticism is weak, so is the critic. If that criticism is strong (not
| abuse, not refusal), then your argument is weak. Being technically
| and mathematically correct is not necessarily strength in an argument.
| You may be quite accurate, but the message is obscured by the bulk of
| presentation.
|
| A Canadian social scientist, Marshall McCluhan, demonstrated that
| identical material presented through different media become different
| messages. For instance, if you were to present you material to a
| class, they would accept it and work through it for understanding. If
| you were to present it to that same group of students in the public
| square, some might scoff, others might wander off with indifference.
| If you were to present it on TV, you probably wouldn't even make it to
| the first commercial. If you presented it on radio, you might have a
| highly interested audience. Same material, different venues,
| different responses.
|
| The same goes here. The nature of newsgroups is with dialog and
| hopefully you exchange correspondence with those who will allow you to
| develop your idea and stick with you to the end. If you attempt to
| make one presentation that answers all questions in one place, it
| violates a social contract that excludes them - except for them to
| accept or reject your work. They are not here to submit. This means
| you have to allow a style that is dialog in nature that allows their
| questions along the way to the end, where you do not find yourself
| wandering down the wrong path. (Think of the Socratic or Platonic
| methods of argument.) Unfortunately there are those who will
| manipulate discussion to the wrong path, or confusion. Dialog over
| time will reveal these individuals. This is why "lurking" is advised
| to newcomers so that they recognize personality with the signatures.
|
| One last point. Nothing is done once here. Nothing is solved.
| Nothing is fixed. The message will need repeating if only because new
| participants have not read the first message. The message may need
| repeating because you did not convince your critics, but they have had
| more time to ponder. This means that you sometimes have to vary your
| style and presentation so that repeating is not ignored. If you
| absolutely need the lengthy, mathematical treatment, then publish it
| at a web site and make a reference to it in your discussion. Offering
| the complete mathematical treatment each time you write here
| automatically limits you and reduces your audience. The craft of
| writing is knowing what to throw away. I generally discard 3/4ths of
| what I write before I hit the send button (some may groan not enough
| was thrown away here ;-)
|
| 73's
| Richard Clark, KB7QHC
  #199   Report Post  
Old September 12th 03, 04:15 PM
Richard Clark
 
Posts: n/a
Default

On Fri, 12 Sep 2003 17:37:26 +0300, "pez" wrote:

And this time
it is related to the Buckmaster site
mentioned by you
and that's all.


Hello,

Buckmaster makes available information that is already part of the
public record. That is the point of licensing so that your activities
are not shrouded in secrecy; but it also confirms you have certain
rights to engage in activities others would not be allowed to do.

This, of course, has nothing to do with posting to a newsgroup, but it
was also your choice to declare your call sign which is related to the
activities here, but it is not necessary to reveal to participate.

73's
Richard Clark, KB7QHC
  #200   Report Post  
Old September 12th 03, 10:06 PM
Richard Clark
 
Posts: n/a
Default

On Fri, 12 Sep 2003 22:11:59 +0300, "pez" wrote:

Dear Mr. Richard Clark,

Do you realize that,
this site is unguarded and open to anyone
who would like to modify your personal data,
even if it is "only" for 48 hours at most,
as it claims?
That is the point.
All of the rest are redundant.

Sincerely yours,

pez
SV7BAX


Hello,

Well that is news, yes.

Perhaps you should write them (Buckmaster) to suggest that they track
the IP of the persons responsible for making those changes. This is a
trivial, technical modification to their server software (I've written
such software for Web servers - probably no more than 5 lines of code
and a database call). Then ask them for that IP number so that you
can register formal complaints against that individual. There are any
number of simple and effective methods to prevent what you describe,
nothing is technically difficult nor impossible. 48 Hours is not
defensible with today's attention growing against identity theft.

73's
Richard Clark, KB7QHC


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