The problem with SCX lights seems to be that SCX tracks run at a slightly lower voltage than those of other makers. When you run SCX cars on those tracks the lights burn out. When you you run regular incandescent lamps at a voltage that is greater than they are made for their life may be shortened, but they do not burn out almost immediately like LEDs do. 3mm white LEDs would be the thing to use. They draw 20 milliamps at 3.5 volts. You will needs to know the track voltage, to be safe you should measure the actual voltage. If you run on several tracks use the highest voltage when you figure the right dropping resistor to use. Here is a caculator for the dropping resistor: http://led.linear1.org/led.wiz
for a 12 volt track wire two LEDs and a 270 ohm resistor in series. For a 14 volt track use a 390 ohm resistor. You only need to use a diode if you are going to use supercapacitor to keep the lights lit when the power is off.
for a 12 volt track wire two LEDs and a 270 ohm resistor in series. For a 14 volt track use a 390 ohm resistor. You only need to use a diode if you are going to use supercapacitor to keep the lights lit when the power is off.
