Which sideband is normally used for 10 meter HF, VHF, and UHF single-sideband communications?
The correct answer is A: Upper sideband. Upper sideband (USB) is normally used for 10 meter HF, VHF, and UHF single-sideband communications. This is a convention in amateur radio - USB is standard for frequencies above 10 MHz (including 10 meters, VHF, and UHF), while lower sideband (LSB) is standard for frequencies below 10 MHz (160, 80, 40 meters). For amateur radio operators, following this convention ensures compatibility - everyone uses the same sideband on the same band, allowing proper communication. Understanding this convention is essential for SSB operation.
Exam Tip
10m, VHF, UHF = Upper sideband. Think 'U'pper sideband for 'U'pper frequencies (above 10 MHz). USB for 10m/VHF/UHF, LSB for 160/80/40m. It's a convention for compatibility.
Memory Aid
"10m, VHF, UHF = Upper sideband. Think 'U'pper sideband for 'U'pper frequencies (above 10 MHz). USB convention: 10m/VHF/UHF use USB, 160/80/40m use LSB."
Real-World Application
On 10 meters (28-29.7 MHz), everyone uses upper sideband. If you transmitted lower sideband, your signal would be on the wrong side of the carrier and other operators wouldn't be able to copy you properly. The same applies to VHF and UHF SSB - USB is the standard, ensuring everyone can communicate.
Key Concepts
Why Other Options Are Wrong
Option B (Lower sideband): Incorrect. LSB is used for frequencies below 10 MHz (160, 80, 40 meters), not for 10 meters, VHF, or UHF. The convention is USB above 10 MHz.
Option C (Suppressed sideband): Incorrect. This describes the technique (suppressing one sideband), not which sideband is used. Both USB and LSB are suppressed sideband modes.
Option D (Inverted sideband): Incorrect. This isn't a standard term. The question asks which sideband is used, not about inversion.
题目解析
The correct answer is A: Upper sideband. Upper sideband (USB) is normally used for 10 meter HF, VHF, and UHF single-sideband communications. This is a convention in amateur radio - USB is standard for frequencies above 10 MHz (including 10 meters, VHF, and UHF), while lower sideband (LSB) is standard for frequencies below 10 MHz (160, 80, 40 meters). For amateur radio operators, following this convention ensures compatibility - everyone uses the same sideband on the same band, allowing proper communication. Understanding this convention is essential for SSB operation.
考试技巧
10m, VHF, UHF = Upper sideband. Think 'U'pper sideband for 'U'pper frequencies (above 10 MHz). USB for 10m/VHF/UHF, LSB for 160/80/40m. It's a convention for compatibility.
记忆口诀
10m, VHF, UHF = Upper sideband. Think 'U'pper sideband for 'U'pper frequencies (above 10 MHz). USB convention: 10m/VHF/UHF use USB, 160/80/40m use LSB.
实际应用示例
On 10 meters (28-29.7 MHz), everyone uses upper sideband. If you transmitted lower sideband, your signal would be on the wrong side of the carrier and other operators wouldn't be able to copy you properly. The same applies to VHF and UHF SSB - USB is the standard, ensuring everyone can communicate.
错误选项分析
Option B (Lower sideband): Incorrect. LSB is used for frequencies below 10 MHz (160, 80, 40 meters), not for 10 meters, VHF, or UHF. The convention is USB above 10 MHz. Option C (Suppressed sideband): Incorrect. This describes the technique (suppressing one sideband), not which sideband is used. Both USB and LSB are suppressed sideband modes. Option D (Inverted sideband): Incorrect. This isn't a standard term. The question asks which sideband is used, not about inversion.
知识点
Upper sideband, SSB conventions, 10 meters, VHF/UHF SSB
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.