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Old March 1st 07, 01:52 AM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 1,614
Default The power explanation

Owen Duffy wrote:
Breaking out of the previous thread to explore the "power explanation" in
a steady state situation:

The scenario for discussion is a transmitter connected to a half wave of
600 ohm lossless transmission line connected to an antenna with a
feedpoint impedance of 70+j0.

The transmitter is rated for 100W output, 100W is developed in the 70 ohm
load, the VSWR on the transmission line is 8.6, the "forward power"
(meaning Vf^2/Zo) on the transmission line is 267W, the "reflected
power" (meaning Vr^2/Zo) on the transmission line is 167W, the DC input
power to the transmitter is 200W.

The questions a

Is there any internal inconsistency in the scenario characterisation, if
so, identify / explain?

What is the heat dissipated in the transmitter (and why)?

What part of the "reflected power" of 167W is dissipated in the
transmitter (and why)?


IMO, you missed the most important questions.

Is the amplitude of the energy stored in the transmission
line when steady-state is reached exactly equal to the
amount it takes to support 267w+167w = 434w of total power?

What happens to the 434w of total steady-state energy stored
in the transmission line when the source is disconnected?
--
73, Cecil http://www.w5dxp.com