Class B Amplifier Operation

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What is the primary advantage of class B amplifiers over class A amplifiers?

Lower output impedance
Increased output power for a given input power (correct)
Higher input impedance
Improved linearity

In a push-pull class B amplifier, what is the purpose of the input transformer?

To provide DC bias voltage
To reduce the output impedance
To increase the output power
To convert the input signal to two out of phase signals (correct)

What is the characteristic of transistor operation in a class B amplifier?

The transistor only conducts during the positive half of the input cycle
The transistor never conducts
The transistor always conducts
The transistor conducts only when the input signal is greater than the base-emitter voltage (correct)

What is the purpose of the second B amplifier in a push-pull configuration?

To amplify the entire input cycle (B) Signup and view all the answers

What type of transistors are used in a complementary symmetry class B amplifier?

npn and pnp transistors (B) Signup and view all the answers

What is the characteristic of the output transformer in a push-pull class B amplifier?

It permits current in both directions (D) Signup and view all the answers

What is the main advantage of class B and class AB amplifiers over class A amplifiers?

Much higher efficiency (D) Signup and view all the answers

What type of amplifier is normally limited to radio frequency applications due to severely distorted output waveforms?

Class C amplifier (D) Signup and view all the answers

What is the purpose of a multistage amplifier arrangement?

To increase the overall voltage gain (C) Signup and view all the answers

What is the characteristic of a direct coupled amplifier?

Has a better low-frequency response (A) Signup and view all the answers

What is the maximum efficiency that can be achieved by a class C amplifier?

100% (C) Signup and view all the answers

What is the distortion that occurs when neither transistor is conducting in a class B amplifier?

Crossover distortion (C) Signup and view all the answers

What is the disadvantage of direct coupling in a multistage amplifier?

Small changes in the DC bias voltage are amplified by the second stage. (D) Signup and view all the answers

What is the purpose of capacitive coupling in a multistage amplifier?

To prevent the DC bias of one stage from affecting that of the other. (C) Signup and view all the answers

What is the main difference between RC coupling and impedance coupling?

The type of component used for coupling. (A) Signup and view all the answers

What is the characteristic of load inductors used in impedance coupling?

They have relatively large amounts of inductance. (C) Signup and view all the answers

What is the advantage of transformer coupling in a multistage amplifier?

It has a high efficiency due to the low resistance of the transformer. (C) Signup and view all the answers

What limits the frequency response of a transformer coupled amplifier?

The inductive reactance of the transformer. (A) Signup and view all the answers