*Question G1E10:
[97.101] Why should an amateur operator normally avoid transmitting on 14.100, 18.110, 21.150, 24.930 and 28.200 MHz?*  

*Correct Answer is  A: A system of propagation beacon stations operates on those frequencies*  

### AI Response: (may contain errors)  

The correct answer to why an amateur operator should normally avoid transmitting on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz is:

**A: A system of propagation beacon stations operates on those frequencies.**

### Explanation:

1. **Why the correct answer is correct:**
   - These specific frequencies are designated for propagation beacons, which are automated stations that transmit signals to help operators determine the propagation conditions of radio waves. Transmitting on these frequencies can interfere with the beacons, disrupting their purpose and potentially causing confusion for operators trying to assess propagation.

2. **Why the other choices are incorrect:**
   - **B: A system of automatic digital stations operates on those frequencies.**
     - This is incorrect because while there are automatic digital stations, the frequencies in question are specifically allocated for propagation beacons, not for digital modes.
   - **C: These frequencies are set aside for emergency operations.**
     - This is incorrect as well; emergency operations have designated frequencies, but the ones listed are not among them. Emergency frequencies are typically found in different bands.
   - **D: These frequencies are set aside for bulletins from the FCC.**
     - This is also incorrect. The FCC does not use these frequencies for bulletins. Instead, they are used for propagation beacons, as mentioned.

### Useful Rules of Thumb:
- Always check the frequency allocations for amateur radio bands to avoid interference with designated services.
- Familiarize yourself with the purpose of specific frequencies within the amateur bands to ensure proper operating practices.

By understanding these designations, you can operate more effectively and responsibly within the amateur radio spectrum.