Power status LED


Two LEDs indicate the power on and off status of bread board power . So it helps to confirm whether the positive and negative rails of the bread board are getting power. Green LED lights at power on and turns off after 3 seconds. Red LED turns on at power off and turns off after 3 seconds. Let us see the circuit

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LED Emergency Lamp


Make this simple  White LED emergency lamp using few components. It can be plugged into the AC socket and it turns on at the moment when power failures. It emits cool white light in the room which is sufficient even for reading purpose. It is powered by a 4.5 volt rechargeable battery and uses 1 watt White LED.

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