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Digital signals

NGSS.MS:
MS‑PS4‑3
,
MS‑PS4.C.1
,
MS‑PS4.C
Review your understanding of digital signals in this free article aligned to NGSS standards.

Key points:

  • Information can be stored in digital or analog form. Digital information is made from a certain set of values, or digits. Analog information is made from possibilities within a range.
  • For example, a digital clock can show time with the exact values 0-9. But the hands on an analog clock can point to any value in the range from 0-12.
A clock shows the numbers 12 colon 59 colon 47 at the top. The letters H R S are below 12, M I N S are below 59 and S E C S are below 47.
A digital clock displays time with exact numbers.
The face of a clock is shown. The numbers 1 to 12 are equally-spaced around the face and marked by tick marks. There are 4 shorter tick marks between each number. There is a short arrow hand that points between 12 and 1. There is a long arrow hand that points between 7 and 8. A long straight hand points between 10 and 11.
An analog clock displays time as any possibility within a range.
  • Information in waves can be transmitted with either digital or analog signals using wave properties like frequency or amplitude.
    • The properties of a digital signal match specific values, or digits in their set of values.
    • The properties of an analog signal can be any value within a range.
  • Digital signals are more reliable because interference or noise can be easily removed from the received signal. However, every change within an analog signal contains some information, so interference or noise can be almost impossible to remove.

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  • eggleston blue style avatar for user dena escot
    "Digital signals are more reliable because interference or noise can be easily removed from the received signal. However, every change within an analog signal contains some information, so interference or noise can be almost impossible to remove." do you mean that interference can be removed from digital but not from analog?
    (2 votes)
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    • aqualine ultimate style avatar for user Wolfy
      Essentially. Digital values are exact, they leave little room for interpretation, but Analog has more room for error, but also, more room for interpretation. Depending on what Analog is being used for, this could be a good thing.
      (2 votes)
  • duskpin ultimate style avatar for user im gonna get a blackhole badge
    *MY first comment omg*
    (2 votes)
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  • blobby green style avatar for user NM
    ok thats just confusing
    (2 votes)
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  • blobby green style avatar for user EmmanuelM
    this i s nice
    (1 vote)
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  • primosaur seed style avatar for user adrianfr
    "Digital signals are more reliable because interference or noise can be easily removed from the received signal. However, every change within an analog signal contains some information, so interference or noise can be almost impossible to remove." do you mean that interference can be removed from digital but not from analog?
    (1 vote)
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  • winston default style avatar for user Richard
    Why is it in the video about Analog vs. digital signals, at timestamp , that instead of having the tens, it has the two multiplied by itself?
    (1 vote)
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  • blobby green style avatar for user MichaelS
    According to the seconds on the clock it would be 13 seconds until PM/AM but since it's yes it would be 13
    (1 vote)
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  • male robot johnny style avatar for user kyra📓
    it's saying 125947
    (1 vote)
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    • sneak peak green style avatar for user s1070307
      Technically it says .47, which means it is AM/PM, one (1) minute until AM/PM, but since we have the (.47) we know that it is actually thirteen (13) seconds until AM/PM. Hope this clears it up for you.
      (0 votes)
  • blobby green style avatar for user Maria Ximena
    So they both are the same but they can tell the time but they are different
    (0 votes)
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  • blobby green style avatar for user madilynhunter
    so interference or noise can be almost impossible to remove." do you mean that interference can be removed from digital but not from analog?
    (0 votes)
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