Aluminum, Stainless Steel, Copper
Apollo Command Module Premodulation Processor (manufactured by Collins Radio Corporation) is of solid state design and modular construction and has redundant circuitry. It weighs 14.5 pounds and is 4.7 by 6 by 10.5 inches and required 12.5 watts of power at 28 volts dc. The Premod Processor provided the interface connection between the spacecraft data-gathering equipment and the S-band RF electronics and was essentially the brains of the telecommunications system. It accomplished signal modulation and demodulation, signal mixing, and the proper switching of signals so that the correct intelligence corresponding to a given mode of operation was transmitted.