Instructables
This night lamp isn't only cheap, it is also very easy to make. All you need are cheap and easy to find electronic parts and a little of soldering knowledge.

If you are one of those who has a roomate and need to work on night but he/her needs to sleep, this lamp is very useful for you. All you need to do is connect your lamp, turn of the light and your roomate can get some sleep, and you're still available too see your keyboard!!!
 
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Step 1: You need:

Picture of You need:
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Tools:
- Hot glue gun (optional)
- Soldering iron
- Solder
- Welding grease
- Cutting pliers

Materials:
- 1 USB male connector
- 1 white light LED
- 1 120 Ohm resistor
- About 20 centimeters of cable for speakers
- Wire of a notebook
- Same size of heat shrink tube (5mm in diameter)
- A small piece of another heat shrink tube (around 10mm in diameter)
 
A tip from my brother: sanding the LED so the light spreads and it will look brighter

Step 2: Connecting the LED

First of all, you must remember that the longest tip from the LED is  the positive side of the led , this is the place where the energy is going to enter so here is where we're going to solder the resitor (it doesn't matter which tip of the resistor you use) to protect the LED.

After that all you have to do is strip the cable and solder it with the LED, normally the red wires are positive (the color won't change the polarity) so we'll use red for positive. In my case, after soldering the wire was vulnerable so I added some adhesive tape to it.


A tip from my brother: sanding the LED so the light spreads and it will look brighter
florlayamp2 years ago
i built one similiar to yours from your instructions but used a 100ohm resistor, it works perfectly with my usb charger but when i plug it in to my computer it shuts the computer off instantly and the computer wont turn back on for 5 mins. any ideas?
The USB port can not deliver the current (I=V/R, 5V/100ohm=500mA) that your circuit is drawing. Typically USB v 1.0 and v 2.0 ports can only deliver 500 mA (http://m.extremetech.com/extremetech/#!/entry/how-usb-charging-works-or-how-to-avoid-blowing-up,4f1ef7bd890708bd1a0104d4).
I figured out why it wasnt working, one of the wires was exposed and making contact with the USB cable shielding. It was making the computer think it was shorted out and it was shut off instantly to avoid damage. :)
chekespeare2 years ago
would have been better if you put another tubbing instead of tape.