How to Put a Resistor on an LED
- 1). Key the circuit's voltage into your calculator. Subtract 2, the LED's voltage, from this value. Divide by .01, the LED's current in amps. The result is the resistor's value in ohms. Obtain the resistor.
- 2). Clip one of the LED's leads down to 1 inch. Clip one of the resistor's leads to 1 inch.
- 3). Overlap the two leads and solder them together. Do not heat the leads with the soldering iron for more than five seconds, as excessive heat can damage the LED. The resistor and LED each now have one uncut lead and one shared lead. Do not connect the shared leads to your circuit; use the uncut leads only.
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