At 6/25/2009 12:10, you wrote:
>That kinda surprises me... how does changing power level affect the match?! The characteristics of the class C RFPA change, in particular the duty cycle. My guess is that as the power output is decreased, the output impedance of the final transistor would go up. Since the output matching circuitry is probably designed for best match at full output power, I'd imagine that mismatch losses would go up as the output power is decreased. That would also partially explain the lower efficiency at reduced output power. Just brainstorming... Bob NO6B
