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Вопрос 534

What is the most efficient location for a loading coil on an electrically short whip?

  1. Near the center of the vertical radiatorПравильный ответ
  2. As low as possible on the vertical radiator
  3. At a voltage maximum
  4. At a voltage null

Объяснение

Current on an electrically short whip is largest at the base and falls to zero at the tip, and only the current actually flowing on the radiator produces radiation. A coil near the middle leaves the high-current section below it intact and raises the current in the section above it, so more of the antenna radiates and radiation resistance goes up.

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Вопрос 534: What is the most efficient location for a loading coil on… · FCC Amateur Extra Class (Element 4) · Questena