Video signals VS Audio signals...

Discussion in 'General Electronics Chat' started by Pixel_Outlaw, Aug 14, 2010.

  1. Pixel_Outlaw

    Thread Starter New Member

    Jun 30, 2010
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    I know that one can record audio signals on a tape player and then play the recorded signal through a speaker but my question is "Is it possible to record video signal through an RCA jack onto an audio tape for playback through a display device?". Seems odd but I just wonder what the difference is, both use the same RCA or 3.5 MM jack. Why will one signal record and play back while the other will not?
     
  2. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Ummm, video signals generally span at least 4 MHz worth of bandwidth and go up from there as the resolution capabilities increase. You just can't record a 4 MHz signal on an audio tape recorder, even the best studio cassette decks rarely go above 17 KHz in response.
     
  3. Pixel_Outlaw

    Thread Starter New Member

    Jun 30, 2010
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    Ok thanks, it makes sense now.
     
  4. studiot

    AAC Fanatic!

    Nov 9, 2007
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    You may like to know that the system for recording audio onto tape is totally different from the videotape system.

    With audio recording the signal is directly impressed as a magnetic trace onto the tape, so the variations in the magnetic state of the tape are a direct copy of the audio signal.

    Mechanical limitations max out the recording frequency at just under 20k as has already been said.

    The higher frequency video signal is recorded by a different method; it is loaded (mixed) onto a carrier and that is recorded. The relative speed between the tape and head is increased by spinning the head as well as moving the tape.

    go well
     
    Last edited: Aug 15, 2010
  5. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Then you have VHS which got their longer lengths by not recording all of the signal information whereas Beta recorded it all. This is why some people had both, if you wanted to copy a tape you recordeed it onto Beta then back to VHS and you wouldn't lose anywhere near as much quality.

    The very first video machines in use at TV stations were only used to play commercials with. They held a dozen or two tape cartridges, each of which held a 30 or 60 second commercial. Later machies that could play half hour reels were primarily used for daily soap operas. You got the whole week's worth of episodes in at the same time then sent them back once the week was over to be reused.

    All the good stuff still came as film.
     
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