What is a benefit of low SWR?
The correct answer is B: Reduced signal loss. A benefit of low SWR is reduced signal loss. When SWR is low (close to 1:1), most of the transmitter power is transferred to the antenna with minimal reflection. High SWR causes significant power reflection, which means less power reaches the antenna and more is lost in the feed line. For amateur radio operators, low SWR ensures maximum power transfer and efficient operation. Understanding this helps explain why antenna tuning is important and why low SWR is desirable.
Exam Tip
Low SWR benefit = reduced signal loss. Think 'L'ow 'S'WR = 'L'ess 'S'ignal loss. More power transfers to antenna, less is reflected and lost. Not about TV interference or antenna wear.
Memory Aid
"Low SWR benefit = reduced signal loss. Think 'L'ow 'S'WR = 'L'ess 'S'ignal loss. More power transfers to antenna, less reflection. Ensures efficient power transfer."
Real-World Application
Your antenna has 1.5:1 SWR. About 96% of your 100-watt transmitter power reaches the antenna, with only 4% lost to reflections. If SWR were 3:1, only about 75% would reach the antenna, with 25% lost. Low SWR means more of your power is actually radiated, improving your signal strength.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Low SWR doesn't directly reduce TV interference - that's controlled by filtering and proper station setup. SWR affects power transfer, not interference.
Option C: Incorrect. Low SWR doesn't reduce antenna wear - antennas don't 'wear' from SWR. Physical damage comes from weather and mechanical stress, not SWR.
Option D: Incorrect. Since A and C are not benefits of low SWR, 'all of the above' cannot be correct. Only reduced signal loss is a direct benefit.
题目解析
The correct answer is B: Reduced signal loss. A benefit of low SWR is reduced signal loss. When SWR is low (close to 1:1), most of the transmitter power is transferred to the antenna with minimal reflection. High SWR causes significant power reflection, which means less power reaches the antenna and more is lost in the feed line. For amateur radio operators, low SWR ensures maximum power transfer and efficient operation. Understanding this helps explain why antenna tuning is important and why low SWR is desirable.
考试技巧
Low SWR benefit = reduced signal loss. Think 'L'ow 'S'WR = 'L'ess 'S'ignal loss. More power transfers to antenna, less is reflected and lost. Not about TV interference or antenna wear.
记忆口诀
Low SWR benefit = reduced signal loss. Think 'L'ow 'S'WR = 'L'ess 'S'ignal loss. More power transfers to antenna, less reflection. Ensures efficient power transfer.
实际应用示例
Your antenna has 1.5:1 SWR. About 96% of your 100-watt transmitter power reaches the antenna, with only 4% lost to reflections. If SWR were 3:1, only about 75% would reach the antenna, with 25% lost. Low SWR means more of your power is actually radiated, improving your signal strength.
错误选项分析
Option A: Incorrect. Low SWR doesn't directly reduce TV interference - that's controlled by filtering and proper station setup. SWR affects power transfer, not interference. Option C: Incorrect. Low SWR doesn't reduce antenna wear - antennas don't 'wear' from SWR. Physical damage comes from weather and mechanical stress, not SWR. Option D: Incorrect. Since A and C are not benefits of low SWR, 'all of the above' cannot be correct. Only reduced signal loss is a direct benefit.
知识点
Low SWR, Signal loss, Power transfer, Antenna efficiency
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.