*Question E7B05:
What can be done to prevent unwanted oscillations in an RF power amplifier?*  

*Correct Answer is  C: Install parasitic suppressors and/or neutralize the stage*  

### AI Response: (may contain errors)  

To prevent unwanted oscillations in an RF power amplifier, the correct approach is to **install parasitic suppressors and/or neutralize the stage**. Here's a breakdown of why this is the correct answer and why the other options are not suitable.

### Correct Answer: C - Install parasitic suppressors and/or neutralize the stage

- **Parasitic Suppressors**: These components help to mitigate the effects of parasitic capacitance and inductance that can lead to unwanted feedback and oscillations. By adding these suppressors, you can stabilize the amplifier and prevent it from oscillating at unintended frequencies.
  
- **Neutralization**: This technique involves adding a compensating circuit to cancel out the unwanted feedback that can cause oscillations. It is particularly useful in high-frequency amplifiers where feedback paths can easily lead to instability.

### Why the Other Choices are Incorrect:

- **A: Tune the stage for minimum loading**  
  - Tuning for minimum loading does not address the root cause of oscillations. In fact, it may lead to increased gain and exacerbate the problem. Proper loading is essential for stable operation, and minimizing it can lead to instability.

- **B: Tune both the input and output for maximum power**  
  - While tuning for maximum power can optimize performance, it does not inherently prevent oscillations. In some cases, maximizing power can actually lead to conditions that promote oscillation, especially if the amplifier is already on the edge of stability.

- **D: Use a phase inverter in the output filter**  
  - A phase inverter is typically used to create a phase shift for specific applications, but it does not directly address the issue of oscillations in an RF power amplifier. It may even introduce additional phase shifts that could worsen instability.

### Summary

To maintain stability in RF power amplifiers, focus on using parasitic suppressors and neutralization techniques. This approach directly targets the feedback mechanisms that can lead to unwanted oscillations, ensuring reliable and stable amplifier performance.