At what time of day is sporadic-E propagation most likely to occur?
The correct answer is D: Between sunrise and sunset. At what time of day is sporadic-E propagation most likely to occur is between sunrise and sunset. Sporadic-E is most common during daylight hours. For amateur radio operators, this is important for sporadic-E operation. Understanding this helps when operating sporadic-E.
Exam Tip
Sporadic-E time of day = between sunrise and sunset. Think 'S'poradic-'E' = 'S'unrise to 'E'vening (daylight). Sporadic-E is most common during daylight hours. Not midnight-sunrise, not sunset-midnight, not sunset-sunrise - just sunrise to sunset.
Memory Aid
"Sporadic-E time of day = between sunrise and sunset. Think 'S'poradic-'E' = 'D'aylight. Sporadic-E is most common during daylight hours. Important for sporadic-E operation."
Real-World Application
Sporadic-E propagation: It's most likely to occur between sunrise and sunset (daylight hours). Sporadic-E activity is driven by solar heating of the E layer, so it's most active during the day. This is the time - between sunrise and sunset.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Between midnight and sunrise isn't when sporadic-E occurs - it's between sunrise and sunset. Midnight to sunrise is wrong.
Option B: Incorrect. Between sunset and midnight isn't when sporadic-E occurs - it's between sunrise and sunset. Sunset to midnight is wrong.
Option C: Incorrect. Between sunset and sunrise isn't when sporadic-E occurs - it's between sunrise and sunset. Sunset to sunrise is wrong.
题目解析
The correct answer is D: Between sunrise and sunset. At what time of day is sporadic-E propagation most likely to occur is between sunrise and sunset. Sporadic-E is most common during daylight hours. For amateur radio operators, this is important for sporadic-E operation. Understanding this helps when operating sporadic-E.
考试技巧
Sporadic-E time of day = between sunrise and sunset. Think 'S'poradic-'E' = 'S'unrise to 'E'vening (daylight). Sporadic-E is most common during daylight hours. Not midnight-sunrise, not sunset-midnight, not sunset-sunrise - just sunrise to sunset.
记忆口诀
Sporadic-E time of day = between sunrise and sunset. Think 'S'poradic-'E' = 'D'aylight. Sporadic-E is most common during daylight hours. Important for sporadic-E operation.
实际应用示例
Sporadic-E propagation: It's most likely to occur between sunrise and sunset (daylight hours). Sporadic-E activity is driven by solar heating of the E layer, so it's most active during the day. This is the time - between sunrise and sunset.
错误选项分析
Option A: Incorrect. Between midnight and sunrise isn't when sporadic-E occurs - it's between sunrise and sunset. Midnight to sunrise is wrong. Option B: Incorrect. Between sunset and midnight isn't when sporadic-E occurs - it's between sunrise and sunset. Sunset to midnight is wrong. Option C: Incorrect. Between sunset and sunrise isn't when sporadic-E occurs - it's between sunrise and sunset. Sunset to sunrise is wrong.
知识点
Sporadic-E propagation, Time of day, Between sunrise and sunset, Daylight hours
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.