Paul Burridge wrote:
On Sat, 3 Jan 2004 16:50:52 -0800, "Tim Wescott"
wrote:


Normally you'd expect the final amplifier to be fairly "stiff" - the output
power should be inversely proportional to the resistor you put on it.


??? Shirley, some mistake.

Both AF and HF power amplifiers generally have a very low output impedance.

Motorola's AN721 app note on impedance matching networks for RF
transistors explains this.

This doesn't apply to QRP output stages, though.

Leon
--
Leon Heller, G1HSM
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