Step 4: Build the LED Boards
Solder 3 LED's in series spaced evenly across the small perfboard. Make sure to check polarity - the long leg is positive. Solder them into their holes, and then twist the leads together and solder them. Leave the legs on the outside untrimmed, and mark the sides for polarity. If you forget which side is positive, bend the leads on the outside in and touch it to a 9v battery. If it lights up, you have done a good job. Mark the positive sides. Make two of these.