On 6 Sep 2003 22:19:39 -0700, (Dr. Slick) wrote:

wrote in message ...

But, going back to the original question, wbat is Pfwd and Prev on a
line with complex Z0?

...Keith

I'd like to know the answer to this question too!

Hi Fellows,

Such intense interest and no comments to SV7DMC for his work to this
matter?

73's
Richard Clark, KB7QHC

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

"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".

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

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".

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