Apollo Command Module PCM (Pulse Code Modulation) Assembly, measuring 14.5″ x 14″ x 9″, with ports on the top identified as "J1" through "J18," with three additional connectors on the side, marked "J20" through "J22." The top and side both bear diagrams identifying the port numbers, and another label on the top reads, "C13-1A101." Mounted on a metal base and in fine condition, with soiling and areas of paint loss where labels were removed. The unit received and sampled analog, parallel digital, and serial digital information, which consists of astronaut biomedical, spacecraft operation, and scientific data. It then converted the data to a single serial output for transmission to Earth. This single-output signal was routed to the Premodulation Processor for transmission to the ground or to Data Storage Equipment.
