What is the approximate bandwidth of an FM voice signal on VHF repeaters?
Less than 500 Hz
About 150 kHz
Between 10 and 15 kHz✓Correct answer
Between 50 and 125 kHz
Explanation
By Carson's rule the bandwidth is about 2 times (deviation plus highest audio frequency), so typical amateur FM with about 5 kHz deviation and 3 kHz audio gives roughly 2 × (5 + 3) = 16 kHz, and narrower deviation gives less. Only the 10 to 15 kHz choice is in that range, which is also why 2 meter repeater channels are spaced 15 kHz apart.