*Question E4D02:
Which of the following describes problems caused by poor dynamic range in a receiver?*  

*Correct Answer is  A: Spurious signals caused by cross modulation and desensitization from strong adjacent signals*  

### AI Response: (may contain errors)  

Poor dynamic range in a receiver can lead to several issues, primarily related to handling strong signals while still being able to detect weak ones. Let's break down the correct answer and why the other choices are incorrect:

### Correct Answer:  
**A: Spurious signals caused by cross modulation and desensitization from strong adjacent signals**

1. **Dynamic Range**: This is the range over which a receiver can effectively process signals, from the weakest to the strongest. A poor dynamic range means the receiver struggles to handle strong signals without affecting its ability to receive weaker ones.
2. **Cross Modulation**: This occurs when a strong signal mixes with another signal within the receiver, creating unwanted spurious signals.
3. **Desensitization**: A strong adjacent signal can overload the receiver, reducing its sensitivity to weaker signals. This is a direct consequence of poor dynamic range.

### Incorrect Answers:

**B: Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband**

- **Oscillator Instability**: This is more related to frequency drift and not directly a result of poor dynamic range. It affects frequency accuracy and stability, not the ability to handle strong and weak signals simultaneously.
- **Opposite Sideband Recovery**: This is an issue related to single sideband (SSB) reception and not directly linked to dynamic range.

**C: Poor weak signal reception caused by insufficient local oscillator injection**

- **Local Oscillator Injection**: This refers to the signal provided by the local oscillator to the mixer in a superheterodyne receiver. Insufficient injection affects conversion gain but is not a direct result of poor dynamic range.

**D: Oscillator instability and severe audio distortion of all but the strongest received signals**

- **Audio Distortion**: While distortion can occur, it is not specifically due to poor dynamic range. Distortion is more often related to issues in the audio processing stages or overloading, not dynamic range limitations.

### Summary

Poor dynamic range primarily affects a receiver's ability to handle strong signals without compromising the reception of weaker ones, leading to issues like cross modulation and desensitization. Understanding these concepts is crucial for diagnosing and improving receiver performance.