I have the problem whittled down.

If I plug in a receiver battery into one of the servo slots, the other servo will work. This means I fried the component that limits the voltage for the servos, from 7.4 volts to whatever is safe for the servos. looking at the circuit board, the trace from the positive battery wire to the positive servo wire is almost a straight shot. There is only one component in line, in the trace. if I jumper over this component, the servos work but with too much voltage. so... I just have to identify this component and replace it. This is a pain. anyone know what component this is? no markings on it, just a brown box, face mounted...