*Question T8D13:
What is FT8?*  

*Correct Answer is  B: A digital mode capable of low signal-to-noise operation*  

### AI Response: (may contain errors)  

FT8 is a digital mode used in amateur radio that is specifically designed for weak signal communication. 

### Correct Answer: 
**B: A digital mode capable of low signal-to-noise operation**

- **Why this is correct:**
  - FT8 is optimized for low signal-to-noise ratios, allowing operators to communicate effectively even when signals are very weak. It uses a structured 15-second transmission format, which helps in decoding signals that are difficult to hear.

### Why the Other Choices are Incorrect:
- **A: A wideband FM voice mode**
  - FT8 is not a voice mode; it is a digital mode that transmits data in a specific format rather than voice audio. Wideband FM is typically used for voice communications, not for digital modes like FT8.

- **C: An eight channel multiplex mode for FM repeaters**
  - FT8 does not involve multiplexing or FM repeaters. It is a digital communication mode that operates on specific frequencies and does not utilize multiple channels in the way described.

- **D: A digital slow-scan TV mode with forward error correction and automatic color compensation**
  - FT8 is not a slow-scan TV mode. Slow-scan TV (SSTV) is used for transmitting images, while FT8 is focused on text-based digital communication. Although FT8 does use error correction, it does not involve color compensation as it is not designed for video transmission.

### Summary:
FT8 is a digital mode that excels in low signal-to-noise environments, making it a popular choice for operators looking to make contacts under challenging conditions. Understanding the characteristics of FT8 and differentiating it from other modes is crucial for the Extra Class exam.