usb power automatic night light.

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Hello, today I'm going to show you how to build easy usb power automatic night light with easy to understand wiring diagram in this video.
The circuit consume just .24 mah per hour and can add up to 5 or more leds (five leds are recommend or just change some resistor value and attach heatsink to output transistor).
As you can see in this video that I used 4  rechargeable battery and got 4.8 volts, so you can use usb charger as power source too.

List of component
2 BD 139 transistors or equivalent transistor
1 100 ohms resistor
1 1000 ohm resistor
1 20,000 ohm resistor
1 photo resistor
1-5 LEDs (the more led the more power consume if you use batteries power souce)

 wiring diagram:




Hope you like it.

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