*Question G2E09:
How do you join a contact between two stations using the PACTOR protocol?*  

*Correct Answer is  C: Joining an existing contact is not possible, PACTOR connections are limited to two stations*  

### AI Response: (may contain errors)  

To understand the PACTOR protocol and why the correct answer is C, let's break down the options:

### Correct Answer: C
**Joining an existing contact is not possible; PACTOR connections are limited to two stations.**

- **Explanation**: PACTOR is a digital communication protocol used in amateur radio that allows for efficient data transmission. Each PACTOR connection is established between two stations only. Once a connection is made, no additional stations can join that contact. This is a fundamental characteristic of the protocol, ensuring that communication is streamlined and efficient.

### Why the Other Choices are Incorrect:

- **A: Send broadcast packets containing your call sign while in MONITOR mode**  
  - **Explanation**: In PACTOR, there is no concept of broadcasting packets to join an existing contact. The protocol is designed for point-to-point communication, meaning that it does not support broadcasting to multiple stations. MONITOR mode is used to listen for signals, not to initiate a connection.

- **B: Transmit a steady carrier until the PACTOR protocol times out and disconnects**  
  - **Explanation**: Transmitting a steady carrier does not facilitate joining a contact. PACTOR requires specific data packets to establish and maintain a connection. Simply transmitting a carrier would not be recognized by the protocol and would not lead to a successful connection.

- **D: Send a NAK code**  
  - **Explanation**: A NAK (Negative Acknowledgment) code is used in data communication to indicate that a received packet was not understood or was erroneous. It does not serve the purpose of joining a contact. Instead, it is part of the error correction process within an established connection.

### Summary
- PACTOR connections are strictly between two stations, making it impossible to join an existing contact.
- Understanding the limitations and functionalities of the PACTOR protocol is crucial for effective communication in amateur radio.

This knowledge will help you answer similar questions on the Extra Class exam.