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Step 7USB TIME!
Take the male USB cable and strip the end of it, you should see red and black wires, and two other colored wires. Cut off the two other colored wires, these are for data transfer and we only need the POWER!
The USB will supply 5V @ 100 mA, so if you aren't using the same LEDs as I am, you can calculate the resistor values needed with OHM's Law
Now, we will have to make our resistors.... using other resistors!
In order to get the correct value with what I had lying around the house, I had to put two resistors in parallel.
If you are using different LEDs than I am, and need different values, use this formula:
R3 = (R1*R2)/(R1+R2) I wanted two 178 ohm resistors and one 200 ohm resistor
(I know that 390/2 = 195, but it's close enough)
Now, put one of the 390s in parallel with one of the 330's and make two of these R3's
Next, put two 390's in parallel with each other to make the 195 ohm resistor
Take the three calculated resistors (178, 178, and 195 ohm) and solder all the leads on one side together, so that the other side can be attached to 3, separate wires. Make the resistor "pack" as small as possible. (look at the photo, it's easier to understand)
Clip off all excess leads on the side that you soldered em' all together.
Now, with the cable stripped and the + and - wires stripped as well, tin the wires and attach the red wire (+) to the resistor "pack" on the end where all three resistors are connected.
Also, extend the black wire a bit, we need it a couple inches longer
Now you are ready to make the base!
The USB will supply 5V @ 100 mA, so if you aren't using the same LEDs as I am, you can calculate the resistor values needed with OHM's Law
Now, we will have to make our resistors.... using other resistors!
In order to get the correct value with what I had lying around the house, I had to put two resistors in parallel.
If you are using different LEDs than I am, and need different values, use this formula:
R3 = (R1*R2)/(R1+R2) I wanted two 178 ohm resistors and one 200 ohm resistor
(I know that 390/2 = 195, but it's close enough)
Now, put one of the 390s in parallel with one of the 330's and make two of these R3's
Next, put two 390's in parallel with each other to make the 195 ohm resistor
Take the three calculated resistors (178, 178, and 195 ohm) and solder all the leads on one side together, so that the other side can be attached to 3, separate wires. Make the resistor "pack" as small as possible. (look at the photo, it's easier to understand)
Clip off all excess leads on the side that you soldered em' all together.
Now, with the cable stripped and the + and - wires stripped as well, tin the wires and attach the red wire (+) to the resistor "pack" on the end where all three resistors are connected.
Also, extend the black wire a bit, we need it a couple inches longer
Now you are ready to make the base!
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Hope that helps, and sorry for posting so late.