They electronically switch and amplify signals by harnessing the unique abilities of semiconductor materials. Their invention has transformed the world of electronics and accelerated our entry into the digital age. Behold – the Transistor!

I learned a lot while making this installment of the MAKE presents series. here’s a few of the information resources I found helpful during my research –

Providing a clear and concise explanation of the transistor proved to be an enjoyable challenge. As always, feel free to leave suggestions, questions, corrections, ideas, etc in the comments!

Download the m4v file or subscribe in iTunes

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MAKE presents: The Capacitor

MAKE presents: The Resistor

MAKE presents: The LED

  • Tim

    We enjoy your videos at A little bit of fun, a little bit of history, a little bit of knowledge and a little bit of hands on. Very nicely done. We are looking forward to more. Keep up the good work. It’s good to start to understand exactly what all those little thingies are doing inside our electronic devices.

    • Collin Cunningham

      Thanks Tim. I’m loving the WREXLabs vids – great stuff!

  • Frenzy

    in about 8 minutes, i learned a year’s worth of electronics! thanks for doing this, it’s extremely helpful for us beginners. i really hope to see one about ohm’s law soon.

  • thunderhammer

    What is the purpose of the 100K resistor in the example circuit in the video? Seems unnecessary, so I must be missing something…

    • jammit

      The 100K is there to simply make the transistor less sensitive to current. Without the 100K, simply bringing your hand close to the wire will cause the LED to flicker because of the 60Hz (or 50Hz) AC mains being picked up. In fact, even without AC mains interference, the LED may glow slightly due to current leaking from collector to base from the resistance of the plastic it’s molded in, or else from current sneaking through the transistor because it’s impossible to make something perfect.

  • vivi

    These little videos are really good, and as Tim said there is something for everybody.

    At 7:31 you mention a phrase to remember the order of the leads of the transistor, but it is valid only for this particular transistor. It might be confusing.

    Frenzy: There is already a video on the resistor, capacitor and diode I think, I’m pretty sure the one on the resistor covers Ohm’s law so you should check the archives.

    thunderhammer: I think the 100k resistor is here to lower the sensitivity of the amplifier.

    • Collin Cunningham

      good point about the pinout – I’ve added an annotation to the vid

  • cyenobite2

    Well done!

  • Michael Una

    I want to know: what is the resistance of a big cookie?

    Excellent infotainment!

    • Collin Cunningham

      don’t know, i already ate it :(

  • failrate

    Thanks, Collin!

  • Anonymous

    RE: MAKE presents: The Transistor
    Better re-check the description for how a PNP transistor works in this clip. A PNP transistor is not on until current is applied.

  • Jason

    REALLY love these, but it looks like the most recent video (Transistor) has gone AWOL.

    Thanks for a great set. I finally feel like I’ve learned something. You explain really well.


  • Anonymous

    This is a great series, I hope it continues on with things like op-amps and simple logic gates. Amazing stuff, keep up the good work!

  • Aditya

    Collin Please share some information about Voltage regulators and Auto and Manual modes of Battery chargers