Rf Power Amplifiers - Tank Circuits & Output Coupling
نویسنده
چکیده
2. The loaded Q factor must be carefully selected. Plate current in a class AB, B, or C amplifier does not flow for the complete period of an AC cycle and the waveform is maintained by the inertia of the tuned circuit. Too low a Q causes waveform distortion and increased generation of harmonics. As Q is increased, circulating current in the tank circuit is also increased and if made too high, it causes excessive IR power loss in the circuit. A loaded Q of 12 is considered optimum although values between four and 20 might have to be tolerated over the tuning range of a multiband amplifier.
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