*Question T8B04:
What mode of transmission is commonly used by amateur radio satellites?*  

*Correct Answer is  D: All these choices are correct*  

### AI Response: (may contain errors)  

The correct answer to the question about the mode of transmission commonly used by amateur radio satellites is **D: All these choices are correct**. Here's why:

1. **Why the correct answer is correct:**
   - Amateur radio satellites can utilize multiple modes of transmission, including:
     - **SSB (Single Sideband)**: This mode is efficient for voice communication and is commonly used in satellite operations.
     - **FM (Frequency Modulation)**: FM is often used for voice communications on satellites, especially for low Earth orbit (LEO) satellites, as it provides good audio quality and is less susceptible to noise.
     - **CW (Continuous Wave)/data**: CW is used for Morse code communication, and various digital modes (like PSK31 or packet radio) are also employed for data transmission. These modes are effective for low bandwidth communications.

2. **Why the other choices are incorrect:**
   - **A: SSB**: While SSB is a valid mode, it is not the only mode used by amateur satellites.
   - **B: FM**: FM is also a valid mode, but again, it is not the only one.
   - **C: CW/data**: This choice is correct for certain applications, but it does not encompass the full range of modes used by satellites.

3. **Useful rules of thumb:**
   - When operating with satellites, it's important to understand the specific capabilities of each satellite, as they may support different modes.
   - Always check the satellite's operational mode before attempting communication to ensure compatibility.

In summary, amateur radio satellites can use SSB, FM, and CW/data, making option D the most comprehensive and correct choice.