*Question G2E07:
Which of the following is required when using FT8?*  

*Correct Answer is  B: Computer time accurate to within approximately 1 second*  

### AI Response: (may contain errors)  

To operate FT8, a digital mode used in amateur radio, accurate timing is crucial. 

1. **Correct Answer: Computer time accurate to within approximately 1 second**  
   - FT8 relies on precise timing to synchronize transmissions between stations. The protocol uses 15-second time slots for sending and receiving messages. If your computer's clock is off by more than 1 second, it can lead to missed opportunities for decoding signals, as the timing of transmissions is critical for successful communication.

2. **Why the other choices are incorrect:**
   - **A: A special hardware modem**  
     - FT8 can be operated using standard sound card interfaces and software, so a special hardware modem is not required.
   - **C: Receiver attenuator set to -12 dB**  
     - While an attenuator can be useful in certain situations to prevent overload, it is not a requirement for FT8 operation. The setting of -12 dB is arbitrary and not specifically needed for FT8.
   - **D: A vertically polarized antenna**  
     - FT8 can be used with various types of antennas, including horizontally polarized ones. The choice of antenna polarization depends on the propagation conditions and the stations being contacted, not specifically on the FT8 mode itself.

3. **Useful Rules of Thumb:**
   - Ensure your computer's clock is synchronized using a time server or software like NTP (Network Time Protocol) to maintain accuracy.
   - Familiarize yourself with the FT8 software settings to optimize your setup for effective communication.

This understanding will help you grasp the requirements for using FT8 effectively in your amateur radio operations.