FCC Extra (2024–2028) — Questions 141–150

E3A13. Which of these emission modes is best for auroral propagation?

以下哪种发射模式最适合极光传播？

E3A14. What are circularly polarized electromagnetic waves?

什么是圆极化电磁波？

E3B01. Where is transequatorial propagation (TEP) most likely to occur?

跨赤道传播（TEP）最可能在何处发生？

E3B02. What is the approximate maximum range for signals using transequatorial propagation?

跨赤道传播的最大距离约为多少？

E3B03. At what time of day is transequatorial propagation most likely to occur?

一天中何时最可能出现跨赤道传播？

E3B04. What are “extraordinary” and “ordinary” waves?

什么是「非常波（extraordinary）」与「寻常波（ordinary）」？

E3B05. Which of the following paths is most likely to support long-distance propagation on 160 meters?

在 160 米波段，哪类路径最有利于远距离传播？

E3B06. On which of the following amateur bands is long-path propagation most frequent?

长路径传播（long-path）在以下哪个业余波段最频繁？

E3B07. What effect does lowering a signal’s transmitted elevation angle have on ionospheric HF skip propagation?

降低信号的发射仰角对电离层 HF 跳跃传播有何影响？

E3B08. How does the maximum range of ground-wave propagation change when the signal frequency is increased?

信号频率升高时，地波传播的最大距离如何变化？