Deep Dive: E7B02
The correct answer is A: An amplifier that uses switching technology to achieve high efficiency. What is a Class D amplifier is an amplifier that uses switching technology to achieve high efficiency. Class D amplifiers switch on/off rapidly for efficiency. For amateur radio operators, this is important for amplifier knowledge. Understanding this helps when working with amplifiers.
Why Other Answers Are Wrong
Option B: Incorrect. Low power amplifier using differential amplifier isn't Class D - Class D uses switching technology. Differential amplifier isn't Class D. Option C: Incorrect. Amplifier using drift-mode FETs isn't Class D - Class D uses switching technology. Drift-mode FETs isn't Class D. Option D: Incorrect. Amplifier biased to be free from distortion isn't Class D - Class D uses switching technology. Free from distortion isn't Class D.
Exam Tip
Class D amplifier = uses switching technology to achieve high efficiency. Think 'C'lass 'D' = 'D'igital switching (switching technology). Class D amplifiers switch on/off rapidly for efficiency. Not differential amplifier, not drift-mode FETs, not free from distortion - just switching technology.
Memory Aid
Class D amplifier = uses switching technology to achieve high efficiency. Think 'C'lass 'D' = 'S'witching. Class D amplifiers switch on/off rapidly for efficiency. Important for amplifier knowledge.
Real-World Example
A Class D amplifier: It's an amplifier that uses switching technology to achieve high efficiency. The amplifier switches rapidly between on and off states, minimizing power dissipation. This is what it is - switching technology for high efficiency.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E7B
Reference: 2024-2028 Question Pool · E7 - Practical Circuits
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E7B topic.