*Question G9B06:
Where should the radial wires of a ground-mounted vertical antenna system be placed?*  

*Correct Answer is  C: On the surface or buried a few inches below the ground*  

### AI Response: (may contain errors)  

The correct answer is **C: On the surface or buried a few inches below the ground**. 

### Explanation of the Correct Answer:
- **Ground-mounted vertical antennas** rely on a good ground system to function effectively. 
- Radial wires act as a part of the antenna system, providing a low-resistance path to ground and improving the antenna's efficiency.
- Placing the radials on the surface or just below the ground helps to maximize their effectiveness by ensuring they are in close proximity to the ground, which enhances the radiation pattern and reduces losses.

### Why the Other Choices are Incorrect:
- **A: As high as possible above the ground**  
  - This is incorrect because placing radials high above the ground reduces their effectiveness. Radials need to be close to the ground to provide a good ground plane for the antenna.

- **B: Parallel to the antenna element**  
  - While radials can be oriented in various ways, they should not be strictly parallel to the antenna element. They need to be spread out in a radial pattern to create a proper ground plane, which is essential for optimal performance.

- **D: At the center of the antenna**  
  - This is incorrect because radials should extend outward from the base of the antenna, not be located at the center. The center of the antenna is where the feed point is located, and radials need to be positioned away from this point to effectively serve their purpose.

### Useful Rules of Thumb:
- **Radial Length**: A common rule of thumb is to make radials at least 1/4 wavelength long for the frequency of operation to ensure good performance.
- **Number of Radials**: More radials generally improve the efficiency of the antenna system. A minimum of 4 to 8 radials is often recommended, but more can provide better results.

By understanding these principles, you can effectively prepare for questions related to ground-mounted vertical antennas on the Extra Class exam.