In article , Cecil Moore
wrote:

John Smith wrote:
If you can't make a SIMPLE statement (or paper), on a concept, which an
average layman can understand, you probably don't understand the
concept(s) yourself ... end of story.

Here's a simple statement he could have made about reflected
power not being lost:

In a conjugately matched system using lossless transmission line:

Source Power = Forward Power - Reflected Power = Load Power

Hello, and in a general case one has to be careful in dealing with the
concepts of "forward" and "reflected" when talking about power. It can
become an issue when source impedance, tranmission line characteristic
impedance, and load impedance all have different values. The "matched"
value corresponding to no reflections might not be the value for maximum
power transfer from source to load. In this general case incident
(forward) voltage or current from the source becomes a function of
mismatch between the source and the reference impedance (e.g. 50 ohms) and
the mismatch between the load and reference. When the source is matched
this dependency vanishes and the incident power is the same as the
"available" power (Vsource^2/(4 * Real part of source impedance)) from the
source.

The source can be "matched" to the input of the transmission line feeding
the load but not be conjugately matched to the transmission line/load
combination.
Conversely, we can have reflections present at the source-line interface
for conjugate match conditions. Sincerely, and 73s from N4GGO,

John Wood (Code 5550) e-mail:
Naval Research Laboratory
4555 Overlook Avenue, SW
Washington, DC 20375-5337

J. B. Wood wrote:
Cecil Moore wrote:
In a conjugately matched system using lossless transmission line:
Source Power = Forward Power - Reflected Power = Load Power

The source can be "matched" to the input of the transmission line feeding
the load but not be conjugately matched to the transmission line/load
combination.

Note that I specified an ideal lossless transmission line.
In a lossless system, if a conjugate match exists anywhere,
a conjugate match exists everywhere. My assertion was a
conceptual statement about an ideal example.

Conversely, we can have reflections present at the source-line interface
for conjugate match conditions.

I was also assuming a 50 ohm source with a 50 ohm Z0-match in a
lossless system. I should have specified such. Here is what I
had in mind.

XMTR---50 ohm coax---+---1/8WL 300 ohm twinlead---(97.3-j283.8)

There is a (close enough) 50 ohm Z0-match at '+' :-)
--
73, Cecil http://www.w5dxp.com
"According to the general theory of relativity,
space without ether is unthinkable." Albert Einstein

Cecil Moore wrote:

...
Note that I specified an ideal lossless transmission line.
In a lossless system, if a conjugate match exists anywhere,
a conjugate match exists everywhere. My assertion was a
conceptual statement about an ideal example.
...


Cecil:

I believe so ...

However, you have been lifting weights with your brain. These things
look elementary to you; your only mistake is you do not strive for even
a simpler example, to let those wishing to, catch that first step ...

The lossless line is a key. Remember those lines of force around a
magnet which can be seen with some iron powder and a paper?

These are being stored within the ether; you are seeing the only feeble
proof of the ethers existence--magnetic lines of force, in that simple
experiment. Remember the plans to store energy in a superconductor
configured in an endless loop? Where do people think that energy is
being stored? In the electrons and other particles? Naaa ... it is
being stored within the ether--in magnetic lines of force ...

You lossless line has no loss, simple. 100% of the power being stored
in the ether is being gotten back from the ether (and your lossless line
is a superconductor.) And, when that condition exists, the workings of
the antenna become a bit more clear (visible) ...

Art says some of this in his "ramblings", most just don't look for it
.... Art just obsfucates beyond recognition (or fubar!)

Regards,
JS