What is meant by the statement that a satellite is operating in U/V mode?
The correct answer is B: The satellite uplink is in the 70 centimeter band and the downlink is in the 2 meter band. A satellite operating in U/V mode means the uplink is in the 70 cm band (UHF) and the downlink is in the 2 m band (VHF). The 'U' stands for UHF (uplink) and 'V' stands for VHF (downlink). This is a common configuration for amateur satellites because it provides good separation between transmit and receive frequencies, reducing interference. For amateur radio operators, understanding U/V mode helps when setting up equipment - you need a UHF transmitter for the uplink and a VHF receiver for the downlink.
Exam Tip
U/V mode = UHF uplink, VHF downlink. Think 'U'/'V' = 'U'plink 'U'HF / 'V'HF 'V'ia downlink. 70 cm (UHF) for uplink, 2 m (VHF) for downlink. Common satellite configuration for good frequency separation.
Memory Aid
"U/V mode = UHF uplink, VHF downlink. Think 'U'/'V' = 'U'plink 'U'HF (70 cm) / 'V'HF 'V'ia downlink (2 m). Common configuration for good frequency separation."
Real-World Application
AO-91 operates in U/V mode: you transmit on 435.250 MHz (70 cm UHF) for the uplink, and receive on 145.960 MHz (2 m VHF) for the downlink. This configuration provides good separation between your transmit and receive frequencies, reducing interference. You need a UHF transmitter and VHF receiver (or a dual-band transceiver) to work this satellite.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. 15m uplink and 10m downlink would be HF bands, not U/V mode. U/V specifically refers to UHF/VHF.
Option C: Incorrect. U/V doesn't refer to ultraviolet frequencies - those are much higher (optical spectrum). U/V means UHF/VHF radio bands.
Option D: Incorrect. U/V mode has specific band assignments (UHF uplink, VHF downlink), not variable frequencies. The bands are fixed, though exact frequencies vary by satellite.
题目解析
The correct answer is B: The satellite uplink is in the 70 centimeter band and the downlink is in the 2 meter band. A satellite operating in U/V mode means the uplink is in the 70 cm band (UHF) and the downlink is in the 2 m band (VHF). The 'U' stands for UHF (uplink) and 'V' stands for VHF (downlink). This is a common configuration for amateur satellites because it provides good separation between transmit and receive frequencies, reducing interference. For amateur radio operators, understanding U/V mode helps when setting up equipment - you need a UHF transmitter for the uplink and a VHF receiver for the downlink.
考试技巧
U/V mode = UHF uplink, VHF downlink. Think 'U'/'V' = 'U'plink 'U'HF / 'V'HF 'V'ia downlink. 70 cm (UHF) for uplink, 2 m (VHF) for downlink. Common satellite configuration for good frequency separation.
记忆口诀
U/V mode = UHF uplink, VHF downlink. Think 'U'/'V' = 'U'plink 'U'HF (70 cm) / 'V'HF 'V'ia downlink (2 m). Common configuration for good frequency separation.
实际应用示例
AO-91 operates in U/V mode: you transmit on 435.250 MHz (70 cm UHF) for the uplink, and receive on 145.960 MHz (2 m VHF) for the downlink. This configuration provides good separation between your transmit and receive frequencies, reducing interference. You need a UHF transmitter and VHF receiver (or a dual-band transceiver) to work this satellite.
错误选项分析
Option A: Incorrect. 15m uplink and 10m downlink would be HF bands, not U/V mode. U/V specifically refers to UHF/VHF. Option C: Incorrect. U/V doesn't refer to ultraviolet frequencies - those are much higher (optical spectrum). U/V means UHF/VHF radio bands. Option D: Incorrect. U/V mode has specific band assignments (UHF uplink, VHF downlink), not variable frequencies. The bands are fixed, though exact frequencies vary by satellite.
知识点
U/V mode, Satellite bands, Uplink and downlink, Satellite configuration
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.