Questenaتمرینی که نشان می‌دهد بعد چه چیزی را مرور کنید
سؤال 228

What causes interference received as a series of carriers at regular intervals across a wide frequency range?

  1. Switch-mode power suppliesپاسخ درست
  2. Radar transmitters
  3. Wireless security camera transmitters
  4. Electric fences

توضیح

A switch-mode supply chops its input at a fixed rate with fast edges, so its noise spectrum is a comb of harmonics of the switching frequency, heard as evenly spaced carriers repeating across a wide range. Radar, wireless cameras and electric fences each produce quite different signatures.

ادامهٔ این آزمون

شروع تمرین
سؤال 228: What causes interference received as a series of carriers… · FCC Amateur Extra Class (Element 4) · Questena