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LED/Transistor night light
This circuit is a great intro to understanding how LDRs (light dependent resistor) and transistors work. It’s a LED light that turns on in the dark and off in the light. Schematic: How it works: LDR: the LDR is a variable resistor that has a high resistance when in dark conditions and a low resistance…
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“Make Electronics”: Alarm Circuit
I have been making my way through Charles Platt’s Make Electronics book and this is one of the circuits involving the use of 555 timer ICs. This will a brief discussion of what the circuit does and how it works. If you want more information on how to build the circuit, I recommend buying Mr.…
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Arduino Piano Keyboard
A simple Arduino keyboard.