What transmitter frequencies would create an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?
The correct answer is A: 146.34 MHz and 146.61 MHz. What transmitter frequencies would create an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz is 146.34 MHz and 146.61 MHz. IMD products: 2×146.52 - 146.34 = 146.70, or 146.61 + 146.52 - 146.34 = 146.79 (close). For amateur radio operators, this is important for understanding IMD. Understanding this helps when troubleshooting interference.
Exam Tip
IMD frequencies creating 146.70 MHz with 146.52 MHz = 146.34 MHz and 146.61 MHz. Think 'I'MD = 'I'nterference 'M'ixing 'D'istortion. IMD products: 2×146.52 - 146.34 = 146.70. Not 146.88/146.34, not 146.10/147.30, not 146.30/146.90 - just 146.34 and 146.61 MHz.
Memory Aid
"IMD frequencies creating 146.70 MHz with 146.52 MHz = 146.34 MHz and 146.61 MHz. Think 'I'MD = '1'46.34 and '1'46.61. IMD products: 2×146.52 - 146.34 = 146.70. Important for understanding IMD."
Real-World Application
A receiver tuned to 146.70 MHz with a nearby station on 146.52 MHz: Transmitter frequencies of 146.34 MHz and 146.61 MHz would create intermodulation-product signals. For example, 2×146.52 - 146.34 = 146.70 MHz. This is the combination - 146.34 MHz and 146.61 MHz.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. 146.88 MHz and 146.34 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.88/146.34 isn't correct.
Option C: Incorrect. 146.10 MHz and 147.30 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.10/147.30 isn't correct.
Option D: Incorrect. 146.30 MHz and 146.90 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.30/146.90 isn't correct.
题目解析
The correct answer is A: 146.34 MHz and 146.61 MHz. What transmitter frequencies would create an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz is 146.34 MHz and 146.61 MHz. IMD products: 2×146.52 - 146.34 = 146.70, or 146.61 + 146.52 - 146.34 = 146.79 (close). For amateur radio operators, this is important for understanding IMD. Understanding this helps when troubleshooting interference.
考试技巧
IMD frequencies creating 146.70 MHz with 146.52 MHz = 146.34 MHz and 146.61 MHz. Think 'I'MD = 'I'nterference 'M'ixing 'D'istortion. IMD products: 2×146.52 - 146.34 = 146.70. Not 146.88/146.34, not 146.10/147.30, not 146.30/146.90 - just 146.34 and 146.61 MHz.
记忆口诀
IMD frequencies creating 146.70 MHz with 146.52 MHz = 146.34 MHz and 146.61 MHz. Think 'I'MD = '1'46.34 and '1'46.61. IMD products: 2×146.52 - 146.34 = 146.70. Important for understanding IMD.
实际应用示例
A receiver tuned to 146.70 MHz with a nearby station on 146.52 MHz: Transmitter frequencies of 146.34 MHz and 146.61 MHz would create intermodulation-product signals. For example, 2×146.52 - 146.34 = 146.70 MHz. This is the combination - 146.34 MHz and 146.61 MHz.
错误选项分析
Option B: Incorrect. 146.88 MHz and 146.34 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.88/146.34 isn't correct. Option C: Incorrect. 146.10 MHz and 147.30 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.10/147.30 isn't correct. Option D: Incorrect. 146.30 MHz and 146.90 MHz doesn't create 146.70 MHz IMD - 146.34 MHz and 146.61 MHz does. 146.30/146.90 isn't correct.
知识点
Intermodulation-product signal, Receiver tuned to 146.70 MHz, Nearby station transmits on 146.52 MHz, Transmitter frequencies, 146.34 MHz and 146.61 MHz
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.