How PIR Motion Sensors Work -- The Learning Circuit 81

How PIR Motion Sensors Work

The Learning Circuit | element14 presents | Project Videos

PIR or Passive Infrared sensors can detect movement by comparing variations in heat radiation of objects in their field of view. In this episode of The Learning Circuit, you can learn more about the different types, how they use lenses to increase their range, and interesting technical details about PIR sensors. Hit play to watch another great lesson from Maker Karen and be sure to check out the followup video where Karen shows how to use a PIR sensor in a circuit by making a motion activated snow globe.

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Parents

airbornesurfer over 5 years ago

Great primer on PIR, Karen!

When I was a kid, I had this science activity book that contained a page that was a Fresnel lens with instructions on using it to cook hot dogs--and a stern warning not to cook anything else!
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makerkaren over 5 years ago in reply to airbornesurfer

Solar cookers are fun! I have an old projection tv screen I salvaged that's waiting for spring, when the sun comes out more often here in the midwest. Don't know what I'm gonna "cook", but it's gonna be fun!
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airbornesurfer over 5 years ago in reply to makerkaren

I always wanted to try to build a solar oven, but was never able to get my hands on a lens that big! I think I remember seeing someone, like, properly baking with one. THAT would be something to see!
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airbornesurfer over 5 years ago in reply to makerkaren

I always wanted to try to build a solar oven, but was never able to get my hands on a lens that big! I think I remember seeing someone, like, properly baking with one. THAT would be something to see!
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Children

DAB over 5 years ago in reply to airbornesurfer

You can bake with the solar oven, but it is very tough to control the heat.
You have to rotate the baking dish so that you get uniform heating.

DAB
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