What is used to suppress radio frequency interference from a line-driven AC motor?
The correct answer is B: A brute-force AC-line filter in series with the motor's power leads. What is used to suppress radio frequency interference from a line-driven AC motor is a brute-force AC-line filter in series with the motor's power leads. AC-line filters suppress RFI from motors. For amateur radio operators, this is important for reducing interference. Understanding this helps when suppressing RFI.
Exam Tip
Suppress RFI from AC motor = brute-force AC-line filter in series with motor's power leads. Think 'R'FI from 'A'C 'M'otor = 'B'rute-'F'orce 'A'C-line 'F'ilter. AC-line filters suppress RFI from motors. Not high-pass filter, not series capacitor, not parallel choke - just brute-force AC-line filter.
Memory Aid
"Suppress RFI from AC motor = brute-force AC-line filter in series with motor's power leads. Think 'R'FI from 'A'C 'M'otor = 'B'rute-'F'orce filter. AC-line filters suppress RFI from motors. Important for reducing interference."
Real-World Application
Suppressing radio frequency interference from a line-driven AC motor: A brute-force AC-line filter in series with the motor's power leads is used. This filter blocks RF noise from the motor from traveling back on the power line. This is what's used - brute-force AC-line filter.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. High-pass filter in series with motor's power leads isn't correct - brute-force AC-line filter is used. High-pass filter isn't the solution.
Option C: Incorrect. Bypass capacitor in series with motor's field winding isn't correct - brute-force AC-line filter is used. Series capacitor isn't the solution.
Option D: Incorrect. Bypass choke in parallel with motor's field winding isn't correct - brute-force AC-line filter is used. Parallel choke isn't the solution.
题目解析
The correct answer is B: A brute-force AC-line filter in series with the motor's power leads. What is used to suppress radio frequency interference from a line-driven AC motor is a brute-force AC-line filter in series with the motor's power leads. AC-line filters suppress RFI from motors. For amateur radio operators, this is important for reducing interference. Understanding this helps when suppressing RFI.
考试技巧
Suppress RFI from AC motor = brute-force AC-line filter in series with motor's power leads. Think 'R'FI from 'A'C 'M'otor = 'B'rute-'F'orce 'A'C-line 'F'ilter. AC-line filters suppress RFI from motors. Not high-pass filter, not series capacitor, not parallel choke - just brute-force AC-line filter.
记忆口诀
Suppress RFI from AC motor = brute-force AC-line filter in series with motor's power leads. Think 'R'FI from 'A'C 'M'otor = 'B'rute-'F'orce filter. AC-line filters suppress RFI from motors. Important for reducing interference.
实际应用示例
Suppressing radio frequency interference from a line-driven AC motor: A brute-force AC-line filter in series with the motor's power leads is used. This filter blocks RF noise from the motor from traveling back on the power line. This is what's used - brute-force AC-line filter.
错误选项分析
Option A: Incorrect. High-pass filter in series with motor's power leads isn't correct - brute-force AC-line filter is used. High-pass filter isn't the solution. Option C: Incorrect. Bypass capacitor in series with motor's field winding isn't correct - brute-force AC-line filter is used. Series capacitor isn't the solution. Option D: Incorrect. Bypass choke in parallel with motor's field winding isn't correct - brute-force AC-line filter is used. Parallel choke isn't the solution.
知识点
Radio frequency interference, Line-driven AC motor, Suppress, Brute-force AC-line filter, Series with motor's power leads
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.