In a Class A amplifier, what percentage of the time does the amplifying device conduct?
The correct answer is A: 100%. In a Class A amplifier, the percentage of time the amplifying device conducts is 100%. Class A amplifiers conduct for the entire input cycle, providing linear amplification. For amateur radio operators, this explains Class A operation. Understanding this helps when selecting amplifier classes.
Exam Tip
Class A conduction = 100% of time. Think 'C'lass 'A' = 'A'lways conducting = '1'00%. Class A amplifiers conduct for entire input cycle. Not 50% (Class B), not >50%<100% (Class AB), not <50% (Class C) - just 100%.
Memory Aid
"Class A conduction = 100% of time. Think 'C'lass 'A' = 'A'lways conducting. Class A amplifiers conduct for entire input cycle. Provides linear amplification but low efficiency."
Real-World Application
A Class A amplifier: The amplifying device conducts for 100% of the input cycle, providing linear amplification with low distortion. This makes Class A ideal for audio and SSB, but it's inefficient (typically 25-50% efficiency) because the device always conducts, even with no signal.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. More than 50% but less than 100% is Class AB - Class A conducts for 100%, not less. Class AB is different.
Option C: Incorrect. 50% is Class B - Class A conducts for 100%, not 50%. Class B is different.
Option D: Incorrect. Less than 50% is Class C - Class A conducts for 100%, not less. Class C is different.
题目解析
The correct answer is A: 100%. In a Class A amplifier, the percentage of time the amplifying device conducts is 100%. Class A amplifiers conduct for the entire input cycle, providing linear amplification. For amateur radio operators, this explains Class A operation. Understanding this helps when selecting amplifier classes.
考试技巧
Class A conduction = 100% of time. Think 'C'lass 'A' = 'A'lways conducting = '1'00%. Class A amplifiers conduct for entire input cycle. Not 50% (Class B), not >50%<100% (Class AB), not <50% (Class C) - just 100%.
记忆口诀
Class A conduction = 100% of time. Think 'C'lass 'A' = 'A'lways conducting. Class A amplifiers conduct for entire input cycle. Provides linear amplification but low efficiency.
实际应用示例
A Class A amplifier: The amplifying device conducts for 100% of the input cycle, providing linear amplification with low distortion. This makes Class A ideal for audio and SSB, but it's inefficient (typically 25-50% efficiency) because the device always conducts, even with no signal.
错误选项分析
Option B: Incorrect. More than 50% but less than 100% is Class AB - Class A conducts for 100%, not less. Class AB is different. Option C: Incorrect. 50% is Class B - Class A conducts for 100%, not 50%. Class B is different. Option D: Incorrect. Less than 50% is Class C - Class A conducts for 100%, not less. Class C is different.
知识点
Class A amplifier, 100% conduction, Full cycle, Amplifier classes
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.