Apollo Command Module (Block II) S-Band Amplifier, measuring approximately 5.75″ x 22″ x 6″, with its Collins label on the end: "S-Band Power Amplifier Equipment, NAA S&ID PN ME478 0066 0009, Contract No. NAS 9-150, Date of Mfr. 6 Feb. 69…Mfd. by Collins Radio Co. for the Apollo Spacecraft, Serial No. 026728070023." The top panel is marked "C28-1A104," and features inset ports marked "J1" through "J5." In very good to fine condition. The Apollo CM's S-band power amplifier equipment was used to amplify the radio frequency output from the S-band transmitters when additional signal strength was required for adequate reception by the ground.
From The Peter Gerry Collection.