What's this? (ESC Questions..)

[What's_nitro?]

Well normally if an ESC doesn't have a BEC circuit to power servos and such it will be labeled "Opto-isolated". This is usually found on high voltage ESCs. I have never come across an ESC that was NOT opto-isolated AND had no BEC...except for those mechanical ones with the resistors.

If you are going to use an external BEC, use a pick/paper clip/razor blade to lift the plastic tab that locks the red wire into the Rx plug of the ESC. Pull the red wire out of the plug, bend it back, and use electrical tape to secure it to the other wires. Make sure the metal connector is insulated by the tape.