QuestenaPráctica que te muestra qué repasar después
Pregunta 177

Which of the following could be a cause of interference covering a wide range of frequencies?

  1. Not using a balun or line isolator to feed balanced antennas
  2. Lack of rectification of the transmitter’s signal in power conductors
  3. Arcing at a poor electrical connectionRespuesta correcta
  4. Using a balun to feed an unbalanced antenna

Explicación

An arc at a corroded or loose connection switches current abruptly and repeatedly, and abrupt current steps have energy spread across an enormous span of frequencies. The result is broadband hash rather than interference on one frequency, which is what distinguishes it from a single unwanted signal.

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