a schottky diode is a diode inserted in the motor circuit bridging the +and - lines to the motor.

The polarity of the diode must be correct or the motor won't run at all. (I happen to have an ESC with the diode wired n in my lap...) The silver band goes toward the + line.

My ESC is a GP C-30, the diode (came with a motor that doesn't require this large an ESC...) is an "SR506 JGD" (what that means.. I have no clue... its going to tell the current and voltage rating ot the diode tosomeone who knows how to read the code.)

What the diode actually does is it aids in recovering power stored in the capacitor bridging the + and - leads at the motor. If you don't use the diode in my motor circuit you get 40% less motor run time. You also get less maximum rpm.

The Capacitors convert RF noise potential of the sparking at the motor commutator into stored energy... the manner in which this is done reduces the spark size. (run an electric drive motor in a drk room without the capacitors... then again with the capacitors. The difference in visible sparks is huge.) Without the diode, the majority of the stored energy is "wasted" combating the next spark pulse.... with the diode it s ported back to the motor and used to make the motor run faster.