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Old June 11th 10, 03:13 PM posted to rec.radio.amateur.antenna
K1TTT K1TTT is offline
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First recorded activity by RadioBanter: Apr 2010
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Default Where does it go? (mismatched power)

On Jun 11, 11:32*am, Richard Fry wrote:
On Jun 11, 6:16*am, Owen Duffy wrote:

*... The transmitter output power is probably different ...


Thank you, Owen.

Do your comments apply to a transmitter designed/adjusted for, and
expecting a 50 + j 0 ohm load?

IOW, if the net output power of such a transmitter (which equals that
dissipated in the load) probably is different with such a mismatch, do
you expect the reason for that to be related to "reflected power?"

RF


NO! NO! NO! the difference is not due to 'reflected power'... any
difference is due to the impedance change seen by the transmitter at
its terminals.

A VERY important method of analyzing sinusoidal steady state response
of a system like a transmission line with a load on the end takes the
load impedance and transforms it using the transmission line equations
(with or without loss) back to the source terminals and then replacing
it with an equivalent impedance. as long as the load is constant and
linear this is a well known and easily proved substitution. you can
then solve for conditions seen by the source ignoring the length of
the line and load and using only a lumped impedance, therefore any
reflected wave is irrelevant when analyzing the response of the
source.