Cable for LED
A 2-pin Molex PicoBlade-compatible cable is used to connect the LED to the Feather M4. Make the following cable for connecting the LED.
2-pin Molex cable length: 4 inches.
LEDs have a specific polarity. The longer leg is the anode or + connection.
Next step involves trimming both legs, so it may be helpful to make a small dot with a permanent marker or paint, so you can keep track of which leg is which.
Right-Angled Pins on LED
Cut to trim the two leads from the LEDs shorter. Using a pair of flat pliers, carefully bend the pins so they're right-angled.
Solder Cable to LED
Solder the red wire to the anode/+ pin (the longer leg before trimming) and the black wire to the cathode/– pin (shorter before trimming).
If you get this backwards, it’s not a disaster, the LED just won’t light. You’ll have an opportunity to test it before everything’s sealed inside the prop, and can make changes if necessary.