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السؤال 312

What is the approximate bandwidth of an FM voice signal on VHF repeaters?

  1. Less than 500 Hz
  2. About 150 kHz
  3. Between 10 and 15 kHzالإجابة الصحيحة
  4. Between 50 and 125 kHz

الشرح

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.

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السؤال 312: What is the approximate bandwidth of an FM voice signal on… · FCC Technician Class (Element 2) · Questena