Do the sensors run of a nominal 7.6v (battery voltage) at the power leads or does the microcontroller step down the voltage? I have found what the voltage on the control lines were but not for the actual power leads.
The center power pin for the Analog / Digital and Interrupts ports is +5 Volts from an internal regulator at 1 Amp Max combined over all these power pins. The center power pin for the Motor ports is + Battery Voltage at 4 Amps Max combined over all these power pins. See the updated Input and Outputs section under the Vex Micro Controller Specifications on the Starter Kit page at http://www.vexlabs.com/vex-robotics-design-system.shtml.