What is reciprocal mixing?
The correct answer is D: Local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. What is reciprocal mixing is local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. LO phase noise mixes with nearby signals, creating interference. For amateur radio operators, this is important for receiver performance. Understanding this helps when troubleshooting interference.
Exam Tip
Reciprocal mixing = LO phase noise mixing with adjacent strong signals to create interference. Think 'R'eciprocal 'M'ixing = 'R'eceiver 'M'ixing problem (LO phase noise). LO phase noise mixes with nearby signals, creating interference. Not out-of-band mixing, not signal cancellation, not digital time slots - just LO phase noise with adjacent signals.
Memory Aid
"Reciprocal mixing = LO phase noise mixing with adjacent strong signals to create interference. Think 'R'eciprocal 'M'ixing = 'L'O phase noise. LO phase noise mixes with nearby signals, creating interference. Important for receiver performance."
Real-World Application
Reciprocal mixing: It's local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. The LO's phase noise sidebands mix with nearby strong signals, creating unwanted interference products that fall on the desired frequency. This is what reciprocal mixing is - LO phase noise interference.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Two out-of-band signals mixing to generate in-band spurious isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Out-of-band mixing isn't reciprocal mixing.
Option B: Incorrect. In-phase signals cancelling in mixer isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Signal cancellation isn't reciprocal mixing.
Option C: Incorrect. Two digital signals combining from alternate time slots isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Digital time slots isn't reciprocal mixing.
题目解析
The correct answer is D: Local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. What is reciprocal mixing is local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. LO phase noise mixes with nearby signals, creating interference. For amateur radio operators, this is important for receiver performance. Understanding this helps when troubleshooting interference.
考试技巧
Reciprocal mixing = LO phase noise mixing with adjacent strong signals to create interference. Think 'R'eciprocal 'M'ixing = 'R'eceiver 'M'ixing problem (LO phase noise). LO phase noise mixes with nearby signals, creating interference. Not out-of-band mixing, not signal cancellation, not digital time slots - just LO phase noise with adjacent signals.
记忆口诀
Reciprocal mixing = LO phase noise mixing with adjacent strong signals to create interference. Think 'R'eciprocal 'M'ixing = 'L'O phase noise. LO phase noise mixes with nearby signals, creating interference. Important for receiver performance.
实际应用示例
Reciprocal mixing: It's local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals. The LO's phase noise sidebands mix with nearby strong signals, creating unwanted interference products that fall on the desired frequency. This is what reciprocal mixing is - LO phase noise interference.
错误选项分析
Option A: Incorrect. Two out-of-band signals mixing to generate in-band spurious isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Out-of-band mixing isn't reciprocal mixing. Option B: Incorrect. In-phase signals cancelling in mixer isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Signal cancellation isn't reciprocal mixing. Option C: Incorrect. Two digital signals combining from alternate time slots isn't reciprocal mixing - reciprocal mixing is LO phase noise mixing with adjacent signals. Digital time slots isn't reciprocal mixing.
知识点
Reciprocal mixing, Local oscillator phase noise, Adjacent strong signals, Create interference, Desired signals
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.