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السؤال 139

What is a typical range for tropospheric duct propagation of microwave signals?

  1. 10 miles to 50 miles
  2. 100 miles to 300 milesالإجابة الصحيحة
  3. 1,200 miles
  4. 2,500 miles

الشرح

Ducts are local weather structures of limited extent, so trapped microwave signals typically travel a few hundred miles — far beyond line of sight but well short of intercontinental distances. Ten to fifty miles is roughly ordinary line of sight and requires no duct at all.

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السؤال 139: What is a typical range for tropospheric duct propagation… · FCC Amateur Extra Class (Element 4) · Questena