*Question T4B03:
How is squelch adjusted so that a weak FM signal can be heard?*  

*Correct Answer is  A: Set the squelch threshold so that receiver output audio is on all the time*  

### AI Response: (may contain errors)  

To understand how to adjust squelch for weak FM signals, let's break down the correct answer and the other options.

### Correct Answer: 
**A: Set the squelch threshold so that receiver output audio is on all the time.**

- **Explanation**: 
  - Squelch is a feature that mutes the audio output of a receiver when the signal is below a certain threshold. By setting the squelch threshold low enough (or disabling it), you allow weak signals to be heard. This means the receiver will output audio continuously, even when the signal is weak, making it possible to hear faint transmissions.

### Why the Other Choices are Incorrect:

- **B: Turn up the audio level until it overcomes the squelch threshold.**
  - **Explanation**: Increasing the audio level does not affect the squelch threshold. If the squelch is set too high, the audio will still be muted regardless of the volume level. This option does not address the need to adjust the squelch itself.

- **C: Turn on the anti-squelch function.**
  - **Explanation**: The term "anti-squelch" is not standard in radio terminology. Typically, squelch functions are designed to mute weak signals, and there is no common feature that would allow for an "anti-squelch" to enable weak signals without adjusting the squelch threshold.

- **D: Enable squelch enhancement.**
  - **Explanation**: Squelch enhancement is not a standard feature in most radios. This option suggests a method to improve squelch performance, but it does not directly address the need to hear weak signals. Adjusting the squelch threshold is the correct method.

### Summary:
- To hear weak FM signals, you need to adjust the squelch threshold to a lower level or disable it, allowing the receiver to output audio continuously. This is crucial for picking up faint transmissions that would otherwise be muted. 

Remember, the key to effective squelch adjustment is understanding that it controls the audio output based on signal strength, and proper adjustment is essential for receiving weak signals.