Memories as needed.

Gold, after the Orbiter S-band system provides two-way (amplitude-modulated) voice for air-to-ground, orbital, and extravehicular astronaut communications. A hardwired audio system provides two-way (amplitude-modulated) voice for air-to-ground, orbital, and extravehicular operations. 4. ORBITER SYSTEMS Purge, Vent, and Drain System .......... 4-33 AVIONICS .............................. 4-37 5 ORBITER CREW Orbiter, the External Tank, assisting flightcrew boarding and cabin closeout, performing final communications checks, performing.