Ok so I got this idea not while showering, but because I’m very high. The story does come from my bathroom though! I have a night light in my bathroom, and I was looking at the night light as I turned off the bathroom light. I’m a big nerd so I remembered that the things that detect light levels are actually diodes wired in reverse. I thought it would be funny to make it flicker by reflecting the light back on the diode, but it didn’t work. That’s when I had this realization

  • Chozo@fedia.io
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    7 months ago

    Modern night lights won’t have this happen, as they have a built-in “buffer” to prevent rapid on/off cycles like that.

    But I do remember having an old night light when I was younger, probably from the late 80s, that you could make flicker by putting your hand in front of the bulb so that the light reflects back onto the sensor, effectively turning it into a very fast Useless Machine.

  • themeatbridge@lemmy.world
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    7 months ago

    Constant voltage LEDs use something called Pulse Width Modulation, or PWM, to simulate dimmed lights. That’s basically what you’re describing.

      • SzethFriendOfNimi@lemmy.world
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        7 months ago

        Like some motors they operate best at a certain duty cycle.

        The issue with some really cheap ones is that it’s obvious.

        It’s also why, if you’re so inclined at Christmas time, led string lights on trees are hard to photograph since you’ll catch some of them on while others are off at the time of the photo.

  • fidodo@lemmy.world
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    7 months ago

    That’s how all ac powered lights work because the current is constantly alternating.

    • rockSlayer@lemmy.worldOP
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      7 months ago

      I was going to protest this, but then I started looking into how ac is converted to dc and realized that it would be cheaper to just let the diodes run on ac.

      oh shit, my stoned ass wasn’t prepared for this

    • rockSlayer@lemmy.worldOP
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      7 months ago

      From this source:

      A phototransistor is a type of bipolar transistor in which the base-collector junction comes into light. This results in the same behavior of a photodiode

      I’m high and I just wanted to post something low effort that I thought was funny. I know it’s more complex than the way I described it.

      Edit: also, diodes are directional. Saying that a photodiode is “a diode wired in reverse” should be the first sign that I know more than what I’m actually saying. All diodes are capable of reacting to light, a photodiode exploits and amplifies the principle.

  • Norgur@kbin.social
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    7 months ago

    Now take an LED light that has the exact opposite frequency to your local power grid and hold it onto the sensor. The night light won’t know what hit it!