Which digital mode is used as a low-power beacon for assessing HF propagation?
The correct answer is A: WSPR. The digital mode used as a low-power beacon for assessing HF propagation is WSPR. WSPR (Weak Signal Propagation Reporter) is designed for low-power propagation testing. For amateur radio operators, this is a valuable propagation tool. Understanding this helps when assessing band conditions.
Exam Tip
Low-power beacon for HF propagation = WSPR. Think 'W'SPR = 'W'eak 'S'ignal 'P'ropagation 'R'eporter. WSPR is designed for low-power propagation testing. Not MFSK16, not PSK31, not SSB-SC - just WSPR.
Memory Aid
"Low-power beacon for HF propagation = WSPR. Think 'W'SPR = 'W'eak 'S'ignal 'P'ropagation 'R'eporter. WSPR is designed for low-power propagation testing. Standard propagation assessment tool."
Real-World Application
You use WSPR (Weak Signal Propagation Reporter) as a low-power beacon to assess HF propagation. WSPR transmits at very low power (e.g., 5 watts) and reports are collected automatically, showing propagation conditions. WSPR is specifically designed for propagation assessment - it's the standard low-power beacon mode.
Key Concepts
Why Other Options Are Wrong
Option B (MFSK16): Incorrect. MFSK16 is a digital mode for communication, not specifically a low-power beacon for propagation testing - WSPR is designed for propagation. MFSK16 is different.
Option C (PSK31): Incorrect. PSK31 is a digital mode for communication, not specifically a low-power beacon for propagation testing - WSPR is designed for propagation. PSK31 is different.
Option D (SSB-SC): Incorrect. SSB-SC is single sideband suppressed carrier (analog), not a digital mode or beacon - WSPR is digital and for propagation. SSB-SC is different.
题目解析
The correct answer is A: WSPR. The digital mode used as a low-power beacon for assessing HF propagation is WSPR. WSPR (Weak Signal Propagation Reporter) is designed for low-power propagation testing. For amateur radio operators, this is a valuable propagation tool. Understanding this helps when assessing band conditions.
考试技巧
Low-power beacon for HF propagation = WSPR. Think 'W'SPR = 'W'eak 'S'ignal 'P'ropagation 'R'eporter. WSPR is designed for low-power propagation testing. Not MFSK16, not PSK31, not SSB-SC - just WSPR.
记忆口诀
Low-power beacon for HF propagation = WSPR. Think 'W'SPR = 'W'eak 'S'ignal 'P'ropagation 'R'eporter. WSPR is designed for low-power propagation testing. Standard propagation assessment tool.
实际应用示例
You use WSPR (Weak Signal Propagation Reporter) as a low-power beacon to assess HF propagation. WSPR transmits at very low power (e.g., 5 watts) and reports are collected automatically, showing propagation conditions. WSPR is specifically designed for propagation assessment - it's the standard low-power beacon mode.
错误选项分析
Option B (MFSK16): Incorrect. MFSK16 is a digital mode for communication, not specifically a low-power beacon for propagation testing - WSPR is designed for propagation. MFSK16 is different. Option C (PSK31): Incorrect. PSK31 is a digital mode for communication, not specifically a low-power beacon for propagation testing - WSPR is designed for propagation. PSK31 is different. Option D (SSB-SC): Incorrect. SSB-SC is single sideband suppressed carrier (analog), not a digital mode or beacon - WSPR is digital and for propagation. SSB-SC is different.
知识点
WSPR, Low-power beacon, HF propagation, Propagation assessment
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.