Apollo Command Module (Block I) Pulse Code Modulation (PCM) Telemetry Equipment Unit #1, measuring 10.25" x 17" x 6.5", with Radiation, Inc. label on the front panel: "PCM Telemetry Equipment Unit 1, NAA ME 901-0083-0001, Collins Part No. 512-2880-004, Type No. 960B-1M, Mfd by Radiation Inc. for Apollo Spacecraft, Serial No. 07120-007-0007." The front panel is also stamped "For Testing Purposes Only." The unit features a number of analog gate modules, all marked with individual serial numbers. Critical signals were supplied by the various spacecraft systems to pulse code modulated (PCM) equipment for transmission to ground stations.
