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Pregunta 488

What is the most common method of reducing key clicks?

  1. Increase keying waveform rise and fall timesRespuesta correcta
  2. Insert low-pass filters at the transmitter output
  3. Reduce keying waveform rise and fall times
  4. Insert high-pass filters at the transmitter output

Explicación

Because the clicks come from envelope transitions that are too fast, the cure is to slow them down, typically by shaping the keying waveform to a few milliseconds of rise and fall. Filters at the transmitter output do not help, since the click sidebands lie close to the carrier and inside the passband.

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Pregunta 488: What is the most common method of reducing key clicks? · FCC Amateur Extra Class (Element 4) · Questena