LEDs need complex wiring sometimes. This is how to test them.
1. Find the positive lead on the LED. This will be the long one.
- You can remember this by positive having more (the positive lead has more length) and the negative having less (the negative lead has less length).
- If you are unsure of the LED specs, you are always safe with a 390 Ohm.
Things You’ll Need
- A button cell battery
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