WEBVTT

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[unclear opening audio]

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Hey, Woz, what you doing?

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Oh, hi, Adabot.

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I was just adding some protection to this circuit.

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Interesting.

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Why does this circuit need protection?

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Well, a circuit needs to be protected for a couple of reasons.

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One example is if I were to connect a battery to this incorrectly,

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then electrical current might flow in the wrong direction

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and damage some of the components.

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Oh, no.

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How do you make sure that doesn't happen?

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Well, we use a diode.

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By placing a diode at the circuit's power input,

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we ensure that the current can only flow in one direction,

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the correct direction that we've designed the circuit to work with.

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So a diode is like a one-way street for electrons?

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Exactly!

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The electrons can only flow through the diode in one direction,

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and they have a really hard time going back the other way.

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The stripe indicates which end of the diode acts like a wall

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to block the electrons.

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Diode protector of circuits.

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Yes, but diodes do more than just protect circuits, Adabot.

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Oh, what else do they do?

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Well, some diodes emit light when we pass current through them.

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We like to call these light-emitting diodes, or LEDs for short.

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Maybe you've heard of them?

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LEDs? I love LEDs.

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I thought so.

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So that's what D stands for in LED. D stands for diode.

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That's right. Well, it looks like this circuit's all done. How about we go test it out?

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Adabot, are you coming?

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Sorry, Woz. I'm an electron in a diode. I only go in one direction.

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Ow.

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Ow.

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Oh, Adabot, let's go.