How can conducted noise from an automobile battery charging system be suppressed?
The correct answer is D: By installing ferrite chokes on the charging system leads. How can conducted noise from an automobile battery charging system be suppressed is by installing ferrite chokes on the charging system leads. Ferrite chokes block RF noise on power leads. For amateur radio operators, this is important for mobile operation. Understanding this helps when reducing mobile noise.
Exam Tip
Suppress conducted noise from auto charging system = install ferrite chokes on charging system leads. Think 'C'onducted 'N'oise = 'C'hokes on 'N'oise source leads. Ferrite chokes block RF noise on power leads. Not series capacitors, not resistor/capacitor at battery, not filters on radio/antenna - just ferrite chokes on charging leads.
Memory Aid
"Suppress conducted noise from auto charging system = install ferrite chokes on charging system leads. Think 'C'onducted 'N'oise = 'F'errite 'C'hokes. Ferrite chokes block RF noise on power leads. Important for mobile operation."
Real-World Application
Suppressing conducted noise from an automobile battery charging system: Install ferrite chokes on the charging system leads. The ferrite chokes block RF noise from traveling along the power leads. This is the method - ferrite chokes on charging system leads.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Installing filter capacitors in series with alternator leads isn't correct - ferrite chokes on leads suppress noise. Series capacitors isn't the method.
Option B: Incorrect. Installing noise suppression resistor and blocking capacitor at battery isn't correct - ferrite chokes on leads suppress noise. Resistor/capacitor at battery isn't the method.
Option C: Incorrect. Installing high-pass filter in series with radio power lead and low-pass filter in parallel with antenna feed line isn't correct - ferrite chokes on leads suppress noise. Filters on radio/antenna isn't the method.
题目解析
The correct answer is D: By installing ferrite chokes on the charging system leads. How can conducted noise from an automobile battery charging system be suppressed is by installing ferrite chokes on the charging system leads. Ferrite chokes block RF noise on power leads. For amateur radio operators, this is important for mobile operation. Understanding this helps when reducing mobile noise.
考试技巧
Suppress conducted noise from auto charging system = install ferrite chokes on charging system leads. Think 'C'onducted 'N'oise = 'C'hokes on 'N'oise source leads. Ferrite chokes block RF noise on power leads. Not series capacitors, not resistor/capacitor at battery, not filters on radio/antenna - just ferrite chokes on charging leads.
记忆口诀
Suppress conducted noise from auto charging system = install ferrite chokes on charging system leads. Think 'C'onducted 'N'oise = 'F'errite 'C'hokes. Ferrite chokes block RF noise on power leads. Important for mobile operation.
实际应用示例
Suppressing conducted noise from an automobile battery charging system: Install ferrite chokes on the charging system leads. The ferrite chokes block RF noise from traveling along the power leads. This is the method - ferrite chokes on charging system leads.
错误选项分析
Option A: Incorrect. Installing filter capacitors in series with alternator leads isn't correct - ferrite chokes on leads suppress noise. Series capacitors isn't the method. Option B: Incorrect. Installing noise suppression resistor and blocking capacitor at battery isn't correct - ferrite chokes on leads suppress noise. Resistor/capacitor at battery isn't the method. Option C: Incorrect. Installing high-pass filter in series with radio power lead and low-pass filter in parallel with antenna feed line isn't correct - ferrite chokes on leads suppress noise. Filters on radio/antenna isn't the method.
知识点
Conducted noise, Automobile battery charging system, Suppress, Ferrite chokes, Charging system leads
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.