The deceptively simple coil proves incredibly useful in the world of electronics – the inductor’s ability to store energy in an electromagnetic field is the key to making transformers, electromagnets, and many more components work. It truly is an awesome device!

I knew little of how inductors worked before starting out on this vid. In fact, none of the circuits I’ve built ever called for them specifically. But after a bit of research, I was honestly amazed to learn how they work. The process of mutual induction even inspired this little action-painting/diagram


As always, feel free to leave a comment with your ideas/experiences/corrections/take on the matter.

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  • cinsel sohbet

    Very good. Thanks..

  • Marc de Vinck

    Another great video Collin…Love it!

  • Odin84gk

    Interesting video. The editing and presentation of these concepts have gotten more professional and interesting. I can’t wait until you get into more challenging concepts, such as core saturation.

  • Anonymous

    How do you figure out how many fewer coils you need on one side of the transformer to drop the voltage a certain amount?

    • Inventorjack

      It’s all about ratios. If you have 100 turns on one side, and 10 on the other, it’s a 100:10 (or 10:1) transformer. So if you input 50 volts on the side with 100 turns, you’ll get 5 volts (1/10th) out the side with 10 turns.

  • Marty

    Great instructional video! I wasn’t able to find any info about how you guys are licensing it, though (if at all). Can we reuse/remix/etc. this content?

  • Mouseclone

    would it be possible to get a air coil video? I have been wondering about how these work for a while now.

    • jammit

      An air coil works the same as a coil with a core, except the air core has less inductance than the one with a core. As an example, if you have a cored inductor with 100 turns, and it measures 100 milli henries, another coil with the same number of turns but without a core might be 100 micro henries. The only thing a core does is to give a place for the magnetic field to stay. If the core is “nice” to magnetic energy and can hold a stronger magnetic field, then there is more potential energy that can be stored in it. I like to think of an inductor as a storage device and converter. It converts electrical power into a magnetic field and store it for a while, and can convert a magnetic field into electrical power.

  • Anonymous

    This was well explained. I hope you continue making these.

  • S

    What is that blue box in the video? What does it do? How do I make one?

  • Inventorjack

    Very nice presentation on inductors, Collin. I like how you break it down so nicely. Trying to get my non-technical friends to watch and learn!

  • Leesam

    Any info on the Square wave generator?

  • Jodex

    Could you make one video like this about crystal oscillators? It would be cool to see one video like that!


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