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سؤال 132

What is one characteristic of VHF signals received via auroral backscatter?

  1. They are often received from 10,000 miles or more
  2. They are distorted, with a characteristic raspy soundپاسخ درست
  3. They occur only during winter nighttime hours
  4. They are generally strongest when your antenna is aimed west

توضیح

Auroral backscatter reflects the signal off the constantly moving, turbulent ionised curtains of the aurora, which spreads the signal in frequency. The result is a distorted, buzzy or raspy sound, and CW is often the only mode that stays readable.

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شروع تمرین
سؤال 132: What is one characteristic of VHF signals received via… · FCC Technician Class (Element 2) · Questena