*Question E1A04:
[97.301, 97.305] May an Extra class operator answer the CQ of a station on 3.601 MHz LSB phone?*  

*Correct Answer is  C: No, the sideband components will extend beyond the edge of the phone band segment*  

### AI Response: (may contain errors)  

To determine whether an Extra class operator can answer a CQ on 3.601 MHz LSB (Lower Sideband) phone, we need to consider the frequency allocations and the nature of sideband emissions.

1. **Correct Answer Explanation (C):**  
   - The 75-meter phone band for Extra class operators in the United States starts at 3.600 MHz. However, when using LSB, the carrier frequency is at the higher end of the signal, and the sideband extends below the carrier frequency.
   - For LSB, the signal bandwidth typically extends below the carrier frequency by approximately 3 kHz. Therefore, if the carrier is at 3.601 MHz, the lower edge of the sideband would extend to about 3.598 MHz.
   - Since 3.598 MHz is below the 3.600 MHz boundary, the sideband components would extend beyond the edge of the phone band segment, making it illegal to transmit.

2. **Why Other Choices Are Incorrect:**
   - **Choice A:** Incorrect because the entire signal, including sideband components, will not be inside the SSB allocation. The sideband extends below 3.600 MHz.
   - **Choice B:** Incorrect because while the displayed frequency (3.601 MHz) is within the 75-meter phone band, the sideband extends below the band edge.
   - **Choice D:** Incorrect because US stations are permitted to use phone emissions below 3.610 MHz, but they must ensure the entire signal, including sidebands, is within the allocated band.

3. **Useful Rule of Thumb:**
   - For LSB, the signal extends approximately 3 kHz below the carrier frequency. Always ensure the entire signal, including sidebands, is within the allocated band.