*Question G9D12:
What is the common name of a dipole with a single central support?*  

*Correct Answer is  A: Inverted V*  

### AI Response: (may contain errors)  

The correct answer to the question is **A: Inverted V**. 

### Explanation of the Correct Answer:
- An **Inverted V** dipole is characterized by having its two ends sloping downwards from a single central support point. This configuration allows for a compact design while still providing good performance for various frequencies. The angle of the dipole arms can be adjusted to optimize the antenna for specific applications.

### Why the Other Choices are Incorrect:
- **B: Inverted L**: 
  - An Inverted L antenna consists of a vertical section and a horizontal section, forming an "L" shape. It is typically used for low-band operations and does not have a single central support with both ends sloping down.

- **C: Sloper**: 
  - A sloper is an antenna that is typically attached to a tower or pole at one end and slopes down to the ground or another support point. It is not symmetrical like the Inverted V and does not have a central support.

- **D: Lazy H**: 
  - A Lazy H antenna is a type of wire antenna that resembles the letter "H" and is used for specific applications, particularly in VHF and UHF. It does not have the same configuration as an Inverted V dipole.

### Useful Rules of Thumb:
- The Inverted V dipole is often used for its ease of installation and good performance across a range of frequencies. 
- The angle of the arms can affect the radiation pattern and impedance; typically, a wider angle can provide better low-angle radiation, which is beneficial for long-distance communication.

In summary, the Inverted V dipole is the only option that fits the description of having a single central support with both ends sloping downwards, making it the correct answer.