Which of the following signal paths is most likely to experience high levels of absorption when the A-index or K-index is elevated?
The correct answer is B: Through the auroral oval. Which of the following signal paths is most likely to experience high levels of absorption when the A-index or K-index is elevated is through the auroral oval. Auroral paths experience high absorption during geomagnetic storms. For amateur radio operators, this is important for understanding propagation during storms. Understanding this helps when operating during disturbed conditions.
Exam Tip
High absorption path when A/K elevated = through auroral oval. Think 'A'/'K' 'E'levated = 'A'uroral 'E'xtreme absorption. Auroral paths experience high absorption during geomagnetic storms. Not transequatorial, not sporadic-E, not NVIS - just auroral oval.
Memory Aid
"High absorption path when A/K elevated = through auroral oval. Think 'A'/'K' 'E'levated = 'A'uroral absorption. Auroral paths experience high absorption during geomagnetic storms. Important for understanding propagation during storms."
Real-World Application
When A-index or K-index is elevated: Signal paths through the auroral oval experience high levels of absorption. The auroral oval is the region where aurora occurs, and during geomagnetic storms, this region has high ionization that absorbs signals. Other paths (transequatorial, sporadic-E, NVIS) don't experience this high absorption. This is the path - through the auroral oval.
Key Concepts
Why Other Options Are Wrong
Option A (Transequatorial): Incorrect. Transequatorial paths don't experience high absorption - auroral oval paths do. Transequatorial isn't the path.
Option C (Sporadic-E): Incorrect. Sporadic-E paths don't experience high absorption - auroral oval paths do. Sporadic-E isn't the path.
Option D (NVIS): Incorrect. NVIS paths don't experience high absorption - auroral oval paths do. NVIS isn't the path.
题目解析
The correct answer is B: Through the auroral oval. Which of the following signal paths is most likely to experience high levels of absorption when the A-index or K-index is elevated is through the auroral oval. Auroral paths experience high absorption during geomagnetic storms. For amateur radio operators, this is important for understanding propagation during storms. Understanding this helps when operating during disturbed conditions.
考试技巧
High absorption path when A/K elevated = through auroral oval. Think 'A'/'K' 'E'levated = 'A'uroral 'E'xtreme absorption. Auroral paths experience high absorption during geomagnetic storms. Not transequatorial, not sporadic-E, not NVIS - just auroral oval.
记忆口诀
High absorption path when A/K elevated = through auroral oval. Think 'A'/'K' 'E'levated = 'A'uroral absorption. Auroral paths experience high absorption during geomagnetic storms. Important for understanding propagation during storms.
实际应用示例
When A-index or K-index is elevated: Signal paths through the auroral oval experience high levels of absorption. The auroral oval is the region where aurora occurs, and during geomagnetic storms, this region has high ionization that absorbs signals. Other paths (transequatorial, sporadic-E, NVIS) don't experience this high absorption. This is the path - through the auroral oval.
错误选项分析
Option A (Transequatorial): Incorrect. Transequatorial paths don't experience high absorption - auroral oval paths do. Transequatorial isn't the path. Option C (Sporadic-E): Incorrect. Sporadic-E paths don't experience high absorption - auroral oval paths do. Sporadic-E isn't the path. Option D (NVIS): Incorrect. NVIS paths don't experience high absorption - auroral oval paths do. NVIS isn't the path.
知识点
Signal paths, High levels of absorption, A-index or K-index elevated, Through auroral oval
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.