*Question E7B01:
For what portion of the signal cycle does each active element in a push-pull, Class AB amplifier conduct?*  

*Correct Answer is  A: More than 180 degrees but less than 360 degrees*  

### AI Response: (may contain errors)  

In a push-pull, Class AB amplifier, each active element (transistor) conducts for a portion of the signal cycle. Let's break down the correct answer and the reasoning behind it.

### Correct Answer: More than 180 degrees but less than 360 degrees

- **Explanation**: 
  - In a Class AB amplifier, each transistor conducts for more than half of the signal cycle (more than 180 degrees) but less than the entire cycle (360 degrees). This is because the transistors are biased to be "on" for a portion of the cycle, allowing for efficient amplification while minimizing crossover distortion. 
  - Typically, each transistor conducts for about 180 to 200 degrees of the cycle, which allows for smooth transitions and reduces distortion.

### Why the Other Choices are Incorrect:

- **Choice A: More than 180 degrees but less than 360 degrees**  
  - This is the correct answer, as explained above.

- **Choice B: Exactly 180 degrees**  
  - This choice implies that each transistor conducts for exactly half the cycle. In a Class AB amplifier, this is not the case because the biasing allows for conduction beyond 180 degrees to improve linearity and reduce distortion.

- **Choice C: The entire cycle**  
  - This choice describes a Class A amplifier, where the transistor conducts for the entire cycle (360 degrees). In Class AB, the conduction is limited to avoid excessive heat and power loss.

- **Choice D: Less than 180 degrees**  
  - This choice suggests that each transistor conducts for less than half the cycle, which would lead to significant distortion and is not characteristic of Class AB operation.

### Summary

In summary, a push-pull, Class AB amplifier allows each active element to conduct for more than 180 degrees but less than 360 degrees of the signal cycle, optimizing performance while minimizing distortion. Understanding the conduction angles of different amplifier classes is crucial for effective circuit design and operation.