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سؤال 305

What type of modulation is commonly used for VHF packet radio transmissions?

  1. FM or PMپاسخ درست
  2. SSB
  3. AM
  4. PSK

توضیح

VHF packet is normally sent by feeding audio tones from a terminal node controller into an ordinary FM voice transceiver, so the signal on the air is frequency or phase modulated. FM is well suited here because packet keying is constant amplitude and FM receivers ignore amplitude variations.

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شروع تمرین
سؤال 305: What type of modulation is commonly used for VHF packet… · FCC Technician Class (Element 2) · Questena