Technician 2026-2030T4B08
What is the advantage of having a choice of receiver filter bandwidths in a multimode transceiver?
B
Answer
Station setup and equipment operation
Type
A
Permits monitoring several modes simultaneously by selecting a separate filter for each mode
B
Permits noise or interference reduction by selecting a bandwidth matching the mode
C
Increases the number of frequencies that can be stored in memory
D
Increases the amount of offset between receive and transmit frequencies
Answer Notes
Different operating modes require different amounts of frequency space (bandwidth). For example, CW (Morse code) uses a very narrow bandwidth of about 500 Hz, while SSB voice uses about 2.4 kHz, and FM voice uses even more.
Having a choice of receiver filter bandwidths allows you to match the receiver's filter to the mode you are using. This blocks out adjacent signals and background noise that fall outside the required bandwidth. If you used a wide filter for a narrow signal like CW, you would hear nearby stations and unnecessary static, making it much harder to copy the desired signal.
Filter bandwidth has nothing to do with memory channels, simultaneous monitoring, or frequency offsets.
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What is a DMR “code plug”?
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How is a specific group of stations selected on a DMR digital voice transceiver?