*Question E1D11:
[97.209] Which amateur stations are eligible to operate as Earth stations?*  

*Correct Answer is  D: Any amateur station, subject to the privileges of the class of operator license held by the control operator*  

### AI Response: (may contain errors)  

To understand which amateur stations are eligible to operate as Earth stations, we need to consider the privileges associated with different amateur radio licenses and the regulations governing Earth station operations.

1. **Correct Answer Explanation:**

   - **Correct Answer: D**: Any amateur station, subject to the privileges of the class of operator license held by the control operator.
     - This is correct because the FCC rules allow any amateur station to operate as an Earth station, provided that the control operator holds a license class that permits operation on the frequencies being used. The privileges of the control operator's license class determine what frequencies and modes can be used.

2. **Why Other Choices Are Incorrect:**

   - **Choice A**: Any amateur licensee who has successfully completed the AMSAT space communications course.
     - This is incorrect because there is no requirement to complete any specific course, such as the AMSAT space communications course, to operate an Earth station. The operation is based on license privileges, not additional courses.

   - **Choice B**: Only those of General, Advanced or Amateur Extra class operators.
     - This is incorrect because Technician class operators can also operate Earth stations, provided they do so within their frequency privileges. The rule does not restrict Earth station operation to only General, Advanced, or Amateur Extra class operators.

   - **Choice C**: Only those of Amateur Extra class operators.
     - This is incorrect because it unnecessarily restricts Earth station operation to Amateur Extra class operators. All license classes, including Technician and General, can operate Earth stations within their allowed frequency bands.

3. **Useful Rules of Thumb:**

   - The key rule is that the control operator's license class determines the frequencies and modes that can be used. This applies to all amateur operations, including Earth stations.
   - Always ensure that operations are conducted within the frequency privileges of the control operator's license class.

By understanding these points, you can see why any amateur station can operate as an Earth station, as long as the control operator adheres to the privileges of their license class.