*Question G8C02:
Which digital mode is used as a low-power beacon for assessing HF propagation?*  

*Correct Answer is  A: WSPR*  

### AI Response: (may contain errors)  

WSPR (Weak Signal Propagation Reporter) is the correct answer for the digital mode used as a low-power beacon for assessing HF propagation.

1. **Why WSPR is correct:**
   - WSPR is specifically designed for weak signal communication and is used to assess HF propagation conditions. It operates with very low power levels, often less than 1 watt, and can decode signals that are well below the noise floor. This makes it ideal for propagation studies.

2. **Why the other choices are incorrect:**
   - **MFSK16:** This is a multi-frequency shift keying mode used for digital communication, but it is not specifically designed for propagation assessment like WSPR.
   - **PSK31:** This is a popular digital mode for real-time keyboard-to-keyboard communication, not for automated beaconing and propagation assessment.
   - **SSB-SC (Single Sideband Suppressed Carrier):** This is a voice mode, not a digital mode, and is not used for beaconing or propagation studies.

3. **Useful Information:**
   - WSPR uses a narrow bandwidth of about 6 Hz, which allows it to detect very weak signals.
   - The mode is part of a network where stations automatically report received signals to a central database, providing a global view of propagation conditions.

Understanding these distinctions helps in identifying the correct mode for specific amateur radio activities.