On this occasion a bit to learn about making a lamp with USB coming from other laptops or portable pc. It can be practiced if the electrical condition of the home in case of outages.
Make an emergency lighting is required once in a while you are preoccupied with your Office work or assignments are possible at the time of the evening, however, the work is unresolved. However, if you already have another backup lighting, this does not need to practice it. Therefore, the schema below is only intended for those of you who do not have a creative or emergency lighting emergency lighting such as flashlights, candles, etc.
Before you assemble the emergency lights should note the order of foot USB, learn first when necessary checks using AVO meter or other. Below is the order of foot USB pin:
Emergency light circuit schematic can be seen here:
The above scheme is quite simple that are required are white led lights as much as 6 pieces, 1 A diode, Capacitor 1nf, 2 resistor (560 ohm and 1 k), and the transistor NPN series 5 volt voltage as a reinforcement. In the picture above uses transistors BC 548.
Good Luck