This is a guide to making a board for under $15 that provides 5 volt power and basic parts used in electronics prototyping.  Most of the parts can be found at radio shack, and still have reasonable prices.  This is useful when prototyping and is good for beginning solderers.

Step 1: Parts and Tools

wire strippers
wire cutters
soldering iron and solder
electrical tape(optional)

5 leds
5 100 ohm resistors
4 position DIP switch
Momentary pushbutton
5 1k ohm resistors
one small piece of perfboard/veroboard/breadboard
13 long female header
assorted wire, 3+ colors would be good
USB cable, one end must be male/A(standard)
2 10k ohm resistors(optional)
light sensitive resistor(CDS photocell)(optional)

I find futurlec.com is also a cheap place for these parts, but shipping will take a few weeks.

Step 2: The Cable

first, cut the cable at the distance you want.
next, strip away the insulation of the cable and the red and black wires.
Bend the wires away from each other, and solder them to the board.

Step 3: The Input- Switches and a Button

The input consists of 4 switches and a button.  Then each have a pull up resistor.
Solder to every switch individually.  If you put the switch so that the metal tabs are up and won, the left and right sides are the two sides of it and are connected.  For each switch or button, solder one side to 5v, then connect the other side to ground through a resistor and to the female header by a wire.

Step 4: Output-LED Lights

Next, solder in the LEDs.  The shorter legs, or cathodes, should all be connected to ground.
The longer legs, or anodes, should each be connected to part of the pin header by a resistor.

Step 5: Optional Analog Input- Photo-sensitive Resistor

This step is optional.
Solder in the photo-resistor.  Connect one side to ground. Connect the other to 5v through 2 parallel 10k ohm resistors.  connect the spot in between them to the female header.  This will allow any micro-controller to sense the light level.

Step 6: Optional- Add a Case

If you want, you can add a case to this project.  Try to attach the USB cable to it.  I wrapped mine in electrical tape except for the inputs and outputs.  Radioshack also makes cases for the board that would work.
I am very confused with this one! the title says its a USB PSU, but there isnt a schematic, and what is the purpose of the switches and LED's??<br><br>Your other problem is that USB ports are current limited to 100ma each, until you plug in a recognised USB device, if that device needs more then 100ma to operate, the computer will then allow 500ma to pass from that port. As this is not a USB device, the computer will not recognise it, and as a result, the max current available from that port will be 100ma. So if you turn on all 5 LED's, assuming each one draws 20ma (often more) you will have exactly ZERO ma for your project.<br><br>So what does it do?

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