What do the terms “L band” and “S band” specify?
The correct answer is A: The 23- and 13-centimeter bands. What the terms 'L band' and 'S band' specify are the 23- and 13-centimeter bands. L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). For amateur radio operators, this is important for satellite operation. Understanding this helps when operating through satellites.
Exam Tip
L band and S band = 23- and 13-centimeter bands. Think 'L'/'S' band = 'L'onger 'S'horter wavelengths (23cm/13cm). L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). Not 2m/70cm, not system types, not sideband - just 23cm and 13cm.
Memory Aid
"L band and S band = 23- and 13-centimeter bands. Think 'L'/'S' band = '2'3cm/'1'3cm. L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). Important for satellite operation."
Real-World Application
L band and S band: L band refers to the 23-centimeter band (approximately 1.2 GHz), and S band refers to the 13-centimeter band (approximately 2.4 GHz). These are microwave bands used for satellite communications. This is what L band and S band specify - the 23- and 13-centimeter bands.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. 2-meter and 70-centimeter bands aren't L/S band - L/S band are 23cm and 13cm. 2m/70cm is wrong.
Option C: Incorrect. FM and digital store-and-forward systems aren't L/S band - L/S band are frequency bands, not system types. System types aren't bands.
Option D: Incorrect. Which sideband to use isn't L/S band - L/S band are frequency bands, not sideband selection. Sideband selection isn't bands.
题目解析
The correct answer is A: The 23- and 13-centimeter bands. What the terms 'L band' and 'S band' specify are the 23- and 13-centimeter bands. L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). For amateur radio operators, this is important for satellite operation. Understanding this helps when operating through satellites.
考试技巧
L band and S band = 23- and 13-centimeter bands. Think 'L'/'S' band = 'L'onger 'S'horter wavelengths (23cm/13cm). L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). Not 2m/70cm, not system types, not sideband - just 23cm and 13cm.
记忆口诀
L band and S band = 23- and 13-centimeter bands. Think 'L'/'S' band = '2'3cm/'1'3cm. L band refers to 23 cm (1.2 GHz), S band refers to 13 cm (2.4 GHz). Important for satellite operation.
实际应用示例
L band and S band: L band refers to the 23-centimeter band (approximately 1.2 GHz), and S band refers to the 13-centimeter band (approximately 2.4 GHz). These are microwave bands used for satellite communications. This is what L band and S band specify - the 23- and 13-centimeter bands.
错误选项分析
Option B: Incorrect. 2-meter and 70-centimeter bands aren't L/S band - L/S band are 23cm and 13cm. 2m/70cm is wrong. Option C: Incorrect. FM and digital store-and-forward systems aren't L/S band - L/S band are frequency bands, not system types. System types aren't bands. Option D: Incorrect. Which sideband to use isn't L/S band - L/S band are frequency bands, not sideband selection. Sideband selection isn't bands.
知识点
L band, S band, 23-centimeter band, 13-centimeter band
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.