Which mode is most commonly used for SSB voice communications in the VHF and UHF bands?
The correct answer is A: Upper sideband. Upper sideband (USB) is most commonly used for SSB voice communications in the VHF and UHF bands. VHF and UHF are above 10 MHz, so USB is the standard convention. For amateur radio operators, understanding this ensures compatibility on VHF/UHF SSB. Everyone uses USB on these bands, allowing proper communication. This is consistent with the convention for frequencies above 10 MHz.
Exam Tip
VHF/UHF SSB = Upper sideband. Think 'U'pper 'S'ideband for 'U'pper frequencies (VHF/UHF). USB is standard for SSB voice on VHF and UHF bands. Consistent with convention for frequencies above 10 MHz.
Memory Aid
"VHF/UHF SSB = Upper sideband. Think 'U'pper 'S'ideband for 'U'pper frequencies. USB convention applies to VHF and UHF SSB voice communications. Consistent with 14 MHz and higher convention."
Real-World Application
You operate SSB on 6 meters (50 MHz, VHF). Everyone uses upper sideband on this band - it's the standard convention. 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. USB ensures compatibility on VHF/UHF SSB.
Key Concepts
Why Other Options Are Wrong
Option B (Lower sideband): Incorrect. LSB is used on frequencies below 10 MHz (160m, 80m, 40m), not on VHF/UHF. USB is standard for VHF/UHF.
Option C (Suppressed sideband): Incorrect. This describes the technique, not which sideband is used. Both USB and LSB are suppressed sideband modes.
Option D (Double sideband): Incorrect. DSB transmits both sidebands, which is inefficient. SSB (single sideband) is standard, and USB is used on VHF/UHF.
题目解析
The correct answer is A: Upper sideband. Upper sideband (USB) is most commonly used for SSB voice communications in the VHF and UHF bands. VHF and UHF are above 10 MHz, so USB is the standard convention. For amateur radio operators, understanding this ensures compatibility on VHF/UHF SSB. Everyone uses USB on these bands, allowing proper communication. This is consistent with the convention for frequencies above 10 MHz.
考试技巧
VHF/UHF SSB = Upper sideband. Think 'U'pper 'S'ideband for 'U'pper frequencies (VHF/UHF). USB is standard for SSB voice on VHF and UHF bands. Consistent with convention for frequencies above 10 MHz.
记忆口诀
VHF/UHF SSB = Upper sideband. Think 'U'pper 'S'ideband for 'U'pper frequencies. USB convention applies to VHF and UHF SSB voice communications. Consistent with 14 MHz and higher convention.
实际应用示例
You operate SSB on 6 meters (50 MHz, VHF). Everyone uses upper sideband on this band - it's the standard convention. 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. USB ensures compatibility on VHF/UHF SSB.
错误选项分析
Option B (Lower sideband): Incorrect. LSB is used on frequencies below 10 MHz (160m, 80m, 40m), not on VHF/UHF. USB is standard for VHF/UHF. Option C (Suppressed sideband): Incorrect. This describes the technique, not which sideband is used. Both USB and LSB are suppressed sideband modes. Option D (Double sideband): Incorrect. DSB transmits both sidebands, which is inefficient. SSB (single sideband) is standard, and USB is used on VHF/UHF.
知识点
Upper sideband, USB, VHF/UHF SSB, SSB conventions
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.