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Old June 8th 04, 12:32 AM
H. Adam Stevens
 
Posts: n/a
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whoa
system is: source - line - load
If there are impedance mismatches, in the steady state (ie 3 microseconds
after key down);
There will be more energy in the transmission line and the source than there
would be if all the impedances were matched.
This is necessary to satisfy the boundary conditions imposed on Maxwell's
Equations at each end of the transmission line.

The losses are the rent you pay for storing the energy; See bazookas for a
good example.

To the radiated energy moving past the probe one must add the losses.

That's why I prefer antennas with no reflections.
Reflect on that.

If you really want a book Paul Dirac's "Quantum Mechanics" is sweet.
Or Hawking's "The Large Scale Structure of Space-Time."


My cat, Hiram P Maxim (Max for short, he likes sleeping on the S-Line I've
had since '63), just walked over the keys and approves.

73
H.
NQ5H


"Jim Kelley" wrote in message
...


Tam/WB2TT wrote:

"Cecil Moore" wrote in message
...
The 'why' is conservation of energy. If there are only two directions
available and energy was traveling in one direction and now it isn't,
it's a no-brainer to realize that it must have changed directions.


Cecil, I think a more convincing argument is that I can take a slotted

line
and directly measure a standing wave on it. A wave traveling in one
direction can not do that. Or am I cunfusing things?

Tam/WB2TT


No. That's right. But the point is - how much energy is actually
moving past the probe? Cecil seems to believe that a standing wave is
more than a superposition of voltages. It would be easy to mistake that
as a superposition of energies. But one can only superpose vector
quantities.

73, Jim AC6XG