Which of the following is used to measure SWR?
The correct answer is D: All these choices are correct. Which of the following is used to measure SWR includes: directional wattmeter, vector network analyzer, and antenna analyzer. All three can measure SWR. For amateur radio operators, this is important for test equipment. Understanding this helps when measuring SWR.
Exam Tip
All three can measure SWR: directional wattmeter, vector network analyzer, antenna analyzer. When all listed instruments can measure SWR, 'all of the above' is usually the answer. All are valid SWR measurement tools.
Memory Aid
"All three can measure SWR: Directional wattmeter, Vector network analyzer, Antenna analyzer. Think 'A'll 'S'WR 'M'easurement tools. All three are valid SWR measurement instruments. Important for test equipment."
Real-World Application
Measuring SWR: A directional wattmeter can measure forward and reflected power to calculate SWR. A vector network analyzer can measure SWR directly. An antenna analyzer can measure SWR and impedance. All three can measure SWR. This is what can measure SWR - all these instruments.
Key Concepts
Why Other Options Are Wrong
Option A: While correct, this is incomplete. Vector network analyzer and antenna analyzer can also measure SWR.
Option B: While correct, this is incomplete. Directional wattmeter and antenna analyzer can also measure SWR.
Option C: While correct, this is incomplete. Directional wattmeter and vector network analyzer can also measure SWR.
题目解析
The correct answer is D: All these choices are correct. Which of the following is used to measure SWR includes: directional wattmeter, vector network analyzer, and antenna analyzer. All three can measure SWR. For amateur radio operators, this is important for test equipment. Understanding this helps when measuring SWR.
考试技巧
All three can measure SWR: directional wattmeter, vector network analyzer, antenna analyzer. When all listed instruments can measure SWR, 'all of the above' is usually the answer. All are valid SWR measurement tools.
记忆口诀
All three can measure SWR: Directional wattmeter, Vector network analyzer, Antenna analyzer. Think 'A'll 'S'WR 'M'easurement tools. All three are valid SWR measurement instruments. Important for test equipment.
实际应用示例
Measuring SWR: A directional wattmeter can measure forward and reflected power to calculate SWR. A vector network analyzer can measure SWR directly. An antenna analyzer can measure SWR and impedance. All three can measure SWR. This is what can measure SWR - all these instruments.
错误选项分析
Option A: While correct, this is incomplete. Vector network analyzer and antenna analyzer can also measure SWR. Option B: While correct, this is incomplete. Directional wattmeter and antenna analyzer can also measure SWR. Option C: While correct, this is incomplete. Directional wattmeter and vector network analyzer can also measure SWR.
知识点
Measure SWR, Directional wattmeter, Vector network analyzer, Antenna analyzer
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.