What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands?
The correct answer is B: Nearby corroded metal connections are mixing and reradiating the broadcast signals. What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands is that nearby corroded metal connections are mixing and reradiating the broadcast signals. Corroded connections can act as nonlinear mixers. For amateur radio operators, this is important for troubleshooting interference. Understanding this helps when identifying interference sources.
Exam Tip
AM broadcast signals generating spurious on MF/HF = nearby corroded metal connections mixing and reradiating. Think 'A'M 'B'roadcast 'S'purious = 'C'oroded 'C'onnections 'M'ixing. Corroded connections can act as nonlinear mixers. Not over-modulation, not skywave, not IF overload - just corroded connections mixing.
Memory Aid
"AM broadcast signals generating spurious on MF/HF = nearby corroded metal connections mixing and reradiating. Think 'A'M 'B'roadcast = 'C'oroded 'M'ixing. Corroded connections can act as nonlinear mixers. Important for troubleshooting interference."
Real-World Application
Local AM broadcast band signals combining to generate spurious signals on MF or HF bands: The cause could be nearby corroded metal connections (like rusty pipes, fences, or gutters) that are mixing and reradiating the broadcast signals. The corrosion creates nonlinear junctions that mix frequencies. This is the cause - corroded connections mixing signals.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Broadcast stations transmitting over-modulated signal isn't the cause - corroded connections mixing signals is the cause. Over-modulation isn't the cause.
Option C: Incorrect. Receiving skywave signals from distant station isn't the cause - corroded connections mixing signals is the cause. Skywave isn't the cause.
Option D: Incorrect. Receiver IF amplifier overload isn't the cause - corroded connections mixing signals is the cause. IF overload isn't the cause.
题目解析
The correct answer is B: Nearby corroded metal connections are mixing and reradiating the broadcast signals. What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands is that nearby corroded metal connections are mixing and reradiating the broadcast signals. Corroded connections can act as nonlinear mixers. For amateur radio operators, this is important for troubleshooting interference. Understanding this helps when identifying interference sources.
考试技巧
AM broadcast signals generating spurious on MF/HF = nearby corroded metal connections mixing and reradiating. Think 'A'M 'B'roadcast 'S'purious = 'C'oroded 'C'onnections 'M'ixing. Corroded connections can act as nonlinear mixers. Not over-modulation, not skywave, not IF overload - just corroded connections mixing.
记忆口诀
AM broadcast signals generating spurious on MF/HF = nearby corroded metal connections mixing and reradiating. Think 'A'M 'B'roadcast = 'C'oroded 'M'ixing. Corroded connections can act as nonlinear mixers. Important for troubleshooting interference.
实际应用示例
Local AM broadcast band signals combining to generate spurious signals on MF or HF bands: The cause could be nearby corroded metal connections (like rusty pipes, fences, or gutters) that are mixing and reradiating the broadcast signals. The corrosion creates nonlinear junctions that mix frequencies. This is the cause - corroded connections mixing signals.
错误选项分析
Option A: Incorrect. Broadcast stations transmitting over-modulated signal isn't the cause - corroded connections mixing signals is the cause. Over-modulation isn't the cause. Option C: Incorrect. Receiving skywave signals from distant station isn't the cause - corroded connections mixing signals is the cause. Skywave isn't the cause. Option D: Incorrect. Receiver IF amplifier overload isn't the cause - corroded connections mixing signals is the cause. IF overload isn't the cause.
知识点
Local AM broadcast band signals, Combining to generate spurious signals, MF or HF bands, Nearby corroded metal connections, Mixing and reradiating
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.