At what point in the solar cycle does the 20-meter band usually support worldwide propagation during daylight hours?
The correct answer is D: At any point. The 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. 20 meters is a reliable band that works throughout the solar cycle, though conditions vary. For amateur radio operators, 20 meters is often called the 'workhorse band' because it's reliable. Understanding this helps when planning operations.
Exam Tip
20m worldwide propagation = at any point in solar cycle. Think '2'0m = '2'eliable at 'A'ny point. 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. Not just solstice, maximum, or minimum - works throughout cycle.
Memory Aid
"20m worldwide propagation = at any point in solar cycle. Think '2'0m = '2'eliable at 'A'ny point. 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. Reliable 'workhorse band.'"
Real-World Application
You operate on 20 meters during solar minimum, solar maximum, and everything in between. The band supports worldwide propagation during daylight hours throughout the solar cycle. Conditions vary (better at maximum, still good at minimum), but the band is reliable. This is why 20 meters is called the 'workhorse band.'
Key Concepts
Why Other Options Are Wrong
Option A (Summer solstice): Incorrect. 20 meters works year-round, not just at summer solstice. Seasonal variations exist, but the band works throughout the year.
Option B (Only at maximum): Incorrect. 20 meters works throughout the solar cycle, not just at solar maximum. It's reliable at all cycle points.
Option C (Only at minimum): Incorrect. 20 meters works throughout the solar cycle, not just at solar minimum. It's reliable at all cycle points.
题目解析
The correct answer is D: At any point. The 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. 20 meters is a reliable band that works throughout the solar cycle, though conditions vary. For amateur radio operators, 20 meters is often called the 'workhorse band' because it's reliable. Understanding this helps when planning operations.
考试技巧
20m worldwide propagation = at any point in solar cycle. Think '2'0m = '2'eliable at 'A'ny point. 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. Not just solstice, maximum, or minimum - works throughout cycle.
记忆口诀
20m worldwide propagation = at any point in solar cycle. Think '2'0m = '2'eliable at 'A'ny point. 20-meter band usually supports worldwide propagation during daylight hours at any point in the solar cycle. Reliable 'workhorse band.'
实际应用示例
You operate on 20 meters during solar minimum, solar maximum, and everything in between. The band supports worldwide propagation during daylight hours throughout the solar cycle. Conditions vary (better at maximum, still good at minimum), but the band is reliable. This is why 20 meters is called the 'workhorse band.'
错误选项分析
Option A (Summer solstice): Incorrect. 20 meters works year-round, not just at summer solstice. Seasonal variations exist, but the band works throughout the year. Option B (Only at maximum): Incorrect. 20 meters works throughout the solar cycle, not just at solar maximum. It's reliable at all cycle points. Option C (Only at minimum): Incorrect. 20 meters works throughout the solar cycle, not just at solar minimum. It's reliable at all cycle points.
知识点
20-meter band, Worldwide propagation, Solar cycle, Reliable band
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.