*Question T2A08:
What is the meaning of the procedural signal “CQ”?*  

*Correct Answer is  D: Calling any station*  

### AI Response: (may contain errors)  

The procedural signal “CQ” is a widely recognized call in amateur radio communications.

1. **Why the correct answer is correct:**
   - The correct answer is **D: Calling any station**. When an operator sends "CQ," they are inviting any station that hears the call to respond. It is a general call to all operators, indicating that the sender is available for a conversation.

2. **Why the other choices are incorrect:**
   - **A: Call on the quarter hour**: This is incorrect because "CQ" does not refer to a specific time or schedule for calling. It is simply a general call.
   - **B: Test transmission, no reply expected**: This is incorrect as "CQ" is not used for test transmissions. It indicates that the operator is looking for a response from any station.
   - **C: Only the called station should transmit**: This is incorrect because "CQ" is not directed at a specific station; it invites any station to respond, not just a particular one.

3. **Useful rules of thumb:**
   - When you hear "CQ," it’s a signal that the operator is looking to make contact with anyone who can hear them.
   - Remember that "CQ" is often followed by the operator's call sign, which identifies who is calling.

Understanding the meaning of "CQ" is essential for effective communication in amateur radio, as it helps facilitate connections between operators.