What type of modulation is used by JT65?
The correct answer is A: Multitone AFSK. What type of modulation is used by JT65 is multitone AFSK. JT65 uses multiple tones with Audio Frequency Shift Keying. For amateur radio operators, this is important for JT65 operation. Understanding this helps when operating JT65.
Exam Tip
JT65 modulation = multitone AFSK. Think 'J'T65 = 'M'ultitone 'A'FSK. JT65 uses multiple tones with Audio Frequency Shift Keying. Not PSK, not RTTY, not QAM - just multitone AFSK.
Memory Aid
"JT65 modulation = multitone AFSK. Think 'J'T65 = 'M'ultitone 'A'FSK. JT65 uses multiple tones with Audio Frequency Shift Keying. Important for JT65 operation."
Real-World Application
JT65 mode: It uses multitone AFSK (Audio Frequency Shift Keying) modulation. JT65 transmits multiple tones simultaneously, with each tone representing different information. This is the modulation type - multitone AFSK is used by JT65.
Key Concepts
Why Other Options Are Wrong
Option B (PSK): Incorrect. PSK isn't used by JT65 - JT65 uses multitone AFSK. PSK isn't the modulation.
Option C (RTTY): Incorrect. RTTY isn't the modulation type - JT65 uses multitone AFSK, not RTTY. RTTY isn't the modulation.
Option D (QAM): Incorrect. QAM isn't used by JT65 - JT65 uses multitone AFSK. QAM isn't the modulation.
题目解析
The correct answer is A: Multitone AFSK. What type of modulation is used by JT65 is multitone AFSK. JT65 uses multiple tones with Audio Frequency Shift Keying. For amateur radio operators, this is important for JT65 operation. Understanding this helps when operating JT65.
考试技巧
JT65 modulation = multitone AFSK. Think 'J'T65 = 'M'ultitone 'A'FSK. JT65 uses multiple tones with Audio Frequency Shift Keying. Not PSK, not RTTY, not QAM - just multitone AFSK.
记忆口诀
JT65 modulation = multitone AFSK. Think 'J'T65 = 'M'ultitone 'A'FSK. JT65 uses multiple tones with Audio Frequency Shift Keying. Important for JT65 operation.
实际应用示例
JT65 mode: It uses multitone AFSK (Audio Frequency Shift Keying) modulation. JT65 transmits multiple tones simultaneously, with each tone representing different information. This is the modulation type - multitone AFSK is used by JT65.
错误选项分析
Option B (PSK): Incorrect. PSK isn't used by JT65 - JT65 uses multitone AFSK. PSK isn't the modulation. Option C (RTTY): Incorrect. RTTY isn't the modulation type - JT65 uses multitone AFSK, not RTTY. RTTY isn't the modulation. Option D (QAM): Incorrect. QAM isn't used by JT65 - JT65 uses multitone AFSK. QAM isn't the modulation.
知识点
JT65, Type of modulation, Multitone AFSK, Audio Frequency Shift Keying
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.