What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?
The correct answer is C: Desensitization. What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency is desensitization. Strong nearby signals reduce receiver sensitivity. For amateur radio operators, this is important for receiver performance. Understanding this helps when troubleshooting receivers.
Exam Tip
Reduction in sensitivity from strong nearby signal = desensitization. Think 'D'esensitization = 'D'iminishes 'S'ensitivity. Strong nearby signals reduce receiver sensitivity. Not reciprocal mixing, not quieting, not cross modulation - just desensitization.
Memory Aid
"Reduction in sensitivity from strong nearby signal = desensitization. Think 'D'esensitization = 'S'ensitivity 'R'eduction. Strong nearby signals reduce receiver sensitivity. Important for receiver performance."
Real-World Application
A strong signal near the received frequency: It causes a reduction in receiver sensitivity, which is called desensitization. The strong signal overloads the receiver front-end, reducing its ability to receive weak signals. This is the term - desensitization.
Key Concepts
Why Other Options Are Wrong
Option A (Reciprocal mixing): Incorrect. Reciprocal mixing is LO phase noise mixing with adjacent signals, not reduction in sensitivity - desensitization is reduction in sensitivity. Reciprocal mixing isn't the term.
Option B (Quieting): Incorrect. Quieting is FM receiver noise reduction, not reduction in sensitivity - desensitization is reduction in sensitivity. Quieting isn't the term.
Option D (Cross modulation interference): Incorrect. Cross modulation is modulation transfer, not reduction in sensitivity - desensitization is reduction in sensitivity. Cross modulation isn't the term.
题目解析
The correct answer is C: Desensitization. What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency is desensitization. Strong nearby signals reduce receiver sensitivity. For amateur radio operators, this is important for receiver performance. Understanding this helps when troubleshooting receivers.
考试技巧
Reduction in sensitivity from strong nearby signal = desensitization. Think 'D'esensitization = 'D'iminishes 'S'ensitivity. Strong nearby signals reduce receiver sensitivity. Not reciprocal mixing, not quieting, not cross modulation - just desensitization.
记忆口诀
Reduction in sensitivity from strong nearby signal = desensitization. Think 'D'esensitization = 'S'ensitivity 'R'eduction. Strong nearby signals reduce receiver sensitivity. Important for receiver performance.
实际应用示例
A strong signal near the received frequency: It causes a reduction in receiver sensitivity, which is called desensitization. The strong signal overloads the receiver front-end, reducing its ability to receive weak signals. This is the term - desensitization.
错误选项分析
Option A (Reciprocal mixing): Incorrect. Reciprocal mixing is LO phase noise mixing with adjacent signals, not reduction in sensitivity - desensitization is reduction in sensitivity. Reciprocal mixing isn't the term. Option B (Quieting): Incorrect. Quieting is FM receiver noise reduction, not reduction in sensitivity - desensitization is reduction in sensitivity. Quieting isn't the term. Option D (Cross modulation interference): Incorrect. Cross modulation is modulation transfer, not reduction in sensitivity - desensitization is reduction in sensitivity. Cross modulation isn't the term.
知识点
Reduction in receiver sensitivity, Strong signal near received frequency, Desensitization, Receiver sensitivity
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.