What is a typical upper frequency limit for low SWR operation of 50-ohm BNC connectors?
The correct answer is C: 4 GHz. The typical upper frequency limit for low SWR operation of 50-ohm BNC connectors is 4 GHz. BNC connectors work well up to about 4 GHz, beyond which performance degrades. For amateur radio operators, this is important when selecting connectors. Understanding this helps when designing RF systems.
Exam Tip
BNC connector upper frequency = 4 GHz. Think 'B'NC = 'B'est 'N'ear 'C'enter (4 GHz). BNC connectors work well up to about 4 GHz for low SWR operation. Not 50 MHz, not 500 MHz, not 40 GHz - just 4 GHz.
Memory Aid
"BNC connector upper frequency = 4 GHz. Think 'B'NC = 'B'est 'N'ear 'C'enter (4 GHz). BNC connectors work well up to about 4 GHz for low SWR operation. Typical upper frequency limit."
Real-World Application
You use BNC connectors in your 2-meter (144 MHz) and 70 cm (440 MHz) equipment. BNC connectors work well up to about 4 GHz, providing low SWR. Beyond 4 GHz, you'd need connectors like SMA or N-type. 4 GHz is the typical upper frequency limit for BNC.
Key Concepts
Why Other Options Are Wrong
Option A (50 MHz): Incorrect. 50 MHz is way too low - BNC connectors work well into the GHz range. 50 MHz is VHF, not the upper limit.
Option B (500 MHz): Incorrect. 500 MHz is too low - BNC connectors work well beyond 500 MHz, up to about 4 GHz. 500 MHz is UHF, not the upper limit.
Option D (40 GHz): Incorrect. 40 GHz is way too high - BNC connectors don't work at 40 GHz. 4 GHz is the typical upper limit.
题目解析
The correct answer is C: 4 GHz. The typical upper frequency limit for low SWR operation of 50-ohm BNC connectors is 4 GHz. BNC connectors work well up to about 4 GHz, beyond which performance degrades. For amateur radio operators, this is important when selecting connectors. Understanding this helps when designing RF systems.
考试技巧
BNC connector upper frequency = 4 GHz. Think 'B'NC = 'B'est 'N'ear 'C'enter (4 GHz). BNC connectors work well up to about 4 GHz for low SWR operation. Not 50 MHz, not 500 MHz, not 40 GHz - just 4 GHz.
记忆口诀
BNC connector upper frequency = 4 GHz. Think 'B'NC = 'B'est 'N'ear 'C'enter (4 GHz). BNC connectors work well up to about 4 GHz for low SWR operation. Typical upper frequency limit.
实际应用示例
You use BNC connectors in your 2-meter (144 MHz) and 70 cm (440 MHz) equipment. BNC connectors work well up to about 4 GHz, providing low SWR. Beyond 4 GHz, you'd need connectors like SMA or N-type. 4 GHz is the typical upper frequency limit for BNC.
错误选项分析
Option A (50 MHz): Incorrect. 50 MHz is way too low - BNC connectors work well into the GHz range. 50 MHz is VHF, not the upper limit. Option B (500 MHz): Incorrect. 500 MHz is too low - BNC connectors work well beyond 500 MHz, up to about 4 GHz. 500 MHz is UHF, not the upper limit. Option D (40 GHz): Incorrect. 40 GHz is way too high - BNC connectors don't work at 40 GHz. 4 GHz is the typical upper limit.
知识点
BNC connector, 4 GHz, Upper frequency limit, Low SWR operation
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.