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Old April 26th 11, 09:34 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default Transmitter Output Impedance

On Apr 26, 10:44*am, Wimpie wrote:
The actual output impedance of the
amplifier is not important in many cases.


Yes, consider a source with 70.7 volts at its output terminals
connected to a 50 ohm load through a 50 ohm feedline. Except for
source efficiency, the source impedance simply doesn't matter. Any
70.7 volt source will deliver 100 watts to the feedline no matter what
the source impedance.

There's a simple method called load-pulling. Keeping everything the
same at the source, if the power to the load increases when the load
is changed away from 50 ohms, the source doesn't have a 50 ohm
internal impedance.
--
73, Cecil, w5dxp.com
"Halitosis is better than no breath at all.", Don, KE6AJH/SK