Halloween Blinking Creature Eyes with LEDs, Arduino, and Laser Cutting
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I made this blinking-creature-eyes lamp as a small gift for my father, who loves to scare neigborhood children during Halloween with a heavily decorated entryway. It's suitable for hiding in foliage, under a chair or couch, in a darkened window, etc. You can make one easily if you have a laser cutter and some way of making printed circuit boards, although a cardboard box with cutout eyes and some LED strip would work just fine as a quick way to get started.
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PCB design in Eagle
This design was heavily determined by parts I happened to have on hand. The LEDs are high-brightness red 5mm devices; I bought a whole sack of these once from Electronics Goldmine (they made an appeance in the Goldfinger laser among other projects). Although I could have controlled the blinking with a 555 timer or similar circuit, I had some surplus Arduino Trinkets from Adafruit, and programmability is nice to have in a project like this one.