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سؤال 145

What makes HF scatter signals often sound distorted?

  1. The ionospheric region involved is unstable
  2. Ground waves are absorbing much of the signal
  3. The E region is not present
  4. Energy is scattered into the skip zone through several different pathsپاسخ درست

توضیح

Scatter delivers the same transmission over several routes of slightly different length, so copies arrive at slightly different times and phases and add destructively at some audio frequencies and constructively at others. That frequency-selective multipath is what the ear hears as distortion.

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شروع تمرین
سؤال 145: What makes HF scatter signals often sound distorted? · FCC General Class (Element 3) · Questena