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Old July 5th 15, 10:19 PM posted to rec.radio.amateur.antenna
Ralph Mowery Ralph Mowery is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 702
Default An antenna question--43 ft vertical


"Roger Hayter" wrote in message
...
The maximum power transfer at equal impedance theorem only applies if

you started with a *fixed* output voltage generator. We don't; we
start with a load impedance (50 ohm resistive), then we decide what
power output we want, and we choose the voltage to be generated
accordingly. (Thank you for giving me the opportunity to think about
this!)


For a transmitter I wold think you start with the tube or transistor and
decide on the power level. From there you start designing the matching
network to go either from the thousand ohm range for a tube or the below
say 10 ohm range for a solid state device depending on the supply voltage
range.

Seems that people are mixing in Norton and Thevenin circuits to explain what
is going on , which is not this case.

As I stated before you are not burning up half the power getting a match in
that equvilent circuit with the series resistor. If this were the case, it
would take a lot more than a DC input of 2000 watts to get 1200 watts out of
the amplifier.