Avionics
Getting the power from the shuttle to the payload required an avionics unit. This unit connected the power from the shuttle to the experiment. The avionics unit also carried the equipment for transmitting the data real-time to the ground control center. The avionics unit also contained the relay switching equipment and had the connections for the customer to use the shuttle television system, and the crew control/display system. Each avionics unit could handle the requirements for six experiments.
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