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سؤال 358

Why is a 19-inch-long vertical antenna often used on 2 meters?

  1. It has high gain
  2. It is a resonant half-wave
  3. It is a resonant quarter-waveپاسخ درست
  4. It has low RF radiation exposure

توضیح

At 146 MHz the wavelength is about 2.05 metres, so a quarter wavelength is roughly 0.51 metres, which is close to 19 or 20 inches once normal end effects are allowed for. A half wave on 2 metres would be about twice that length.

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شروع تمرین
سؤال 358: Why is a 19-inch-long vertical antenna often used on 2… · FCC Technician Class (Element 2) · Questena