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Вопрос 524

What is the approximate feed point impedance at the center of a two-wire half-wave folded dipole antenna?

  1. 300 ohmsПравильный ответ
  2. 72 ohms
  3. 50 ohms
  4. 450 ohms

Объяснение

A folded dipole carries the same total power but divides the current between two parallel conductors, which steps the feed point impedance up by a factor of four. Four times the roughly 72 ohms of a plain half-wave dipole is about 300 ohms, which is why 300-ohm twinlead suits it.

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Вопрос 524: What is the approximate feed point impedance at the center… · FCC Amateur Extra Class (Element 4) · Questena