[Jon Stratis]

As Alan said, I don't think a diode would be legal. This is something we always cripple check, every single year. The stripe on the wire can be hard to see, and it's easy to forget what it indicates, so everyone on the electrical team does a visual verification when it's first hooked up. We ALWAYS check continuity with both the center and outside of the plug to ensure its wires correctly. Then, when we do the initial power on, the radio starts unplugged and we verify voltage on the plug before plugging it in.