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3D render of old tv set with animated static on its screen, as if tuned to a dead channel.

  • jeffw@lemmy.world
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    11 个月前

    Waves are everywhere. The TV picks up whatever waves it can. Some of those waves are signals meant to transmit an image (eg from a broadcast tower), others are just random noise in our environment.

    Not an expert, but that was my understanding

    • ALostInquirer@lemm.eeOP
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      11 个月前

      It’s been awhile since I’ve messed about with this, so I don’t remember (and you may not either, so this is an open question), but wouldn’t it produce the effect even if disconnected from an antenna?

      If so…Would the same principle be in play of it picking up on general EM waves to cause the effect?

      • algorithmae@lemmy.sdf.org
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        11 个月前

        Yeah, the same way a radio tuned to a station could be static until you plug in an antenna.

        You could also get hums and interference from other sufficiently strong EMF sources, like how AM radios can pick up the sound of transmission lines

        • dohpaz42@lemmy.world
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          11 个月前

          Your mom (or dad) using an electric knife to cut a turkey on thanksgiving would do the same. It was wild.

        • lemmy689@lemmy.sdf.org
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          11 个月前

          AM car radio can pick up the waves from your cars electrical alternator as well, which can cause the static to rise and fall in pitch as you speed up and slow down.

      • BarqsHasBite@lemmy.ca
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        11 个月前

        Afaik the antenna is picking up the background waves/radiation and the TV is displaying that background waves/radiation. If you disconnect the antenna, the TV will have no signal to display, it’ll be as blank as it can get.

        • linearchaos@lemmy.world
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          11 个月前

          Nah, the antenna is tuned to pick up vhf/uhf, but the wire / traces and even the legs of the amplifier are sufficient to pick up cmb

      • Kalkaline @leminal.space
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        11 个月前

        The display on the screen is the strongest signal. Without a strong signal from a TV tower, you just get noise from 60 Hz AC running through the wall, or radio towers, or power lines, or whatever else makes that radio noise.