*Question E9C04:
What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?*  

*Correct Answer is  B: Additional lobes form with major lobes increasingly aligned with the axis of the antenna*  

### AI Response: (may contain errors)  

When considering the radiation pattern of an unterminated long wire antenna, it's important to understand how the length of the antenna affects its performance.

### Correct Answer Explanation:
**B: Additional lobes form with major lobes increasingly aligned with the axis of the antenna.**

- As the length of the long wire antenna increases, the number of lobes in the radiation pattern also increases. This is due to the antenna becoming more resonant at multiple frequencies, which leads to the formation of additional radiation lobes.
- The major lobes become more aligned with the axis of the antenna, meaning that the radiation is concentrated more in the direction along the length of the wire.

### Incorrect Answer Explanations:
**A: Fewer lobes form with the major lobes increasing closer to broadside to the wire.**
- This is incorrect because increasing the length of the antenna does not reduce the number of lobes; instead, it increases them. The major lobes do not move closer to broadside; they align more with the axis.

**C: The elevation angle increases, and the front-to-rear ratio decreases.**
- This is incorrect because while the elevation angle may change, the front-to-rear ratio typically improves with longer antennas, as the directivity increases. A longer antenna tends to radiate more effectively in the forward direction.

**D: The elevation angle increases, while the front-to-rear ratio is unaffected.**
- This is also incorrect. The elevation angle may not necessarily increase significantly, and the front-to-rear ratio is generally affected positively (improves) with longer antennas.

### Useful Concepts:
- **Radiation Pattern**: The distribution of radiated energy from the antenna in space.
- **Lobes**: Regions of maximum radiation; as the antenna length increases, the number of lobes increases.
- **Antenna Gain**: The ability of the antenna to direct radio frequency energy in a particular direction compared to a reference antenna.

In summary, as the length of an unterminated long wire antenna increases, you will see more lobes forming, and these lobes will align more closely with the antenna's axis, enhancing its directivity.